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Diet

Neu5Gc featured article

N-glycolylneuraminic acid, or Neu5Gc, is a sialic acid – a nine-carbon sugar molecule – produced by most nonhuman mammals. Sialic acids serve diverse roles, such as mediating cell-to-cell interactions, triggering cell signaling cascades, and binding to pathogens. Humans do not produce Neu5Gc; however, trace amounts of the compound are commonly present in human urine, suggesting that Neu5Gc is obtained in the diet. Foods highest in Neu5Gc include red meat and milk. It is rarely present in fish or poultry, but eggs are rich in Neu5Ac.

Neu5Gc is similar in structure to Neu5Ac, a sialic acid produced in the human body. Due to this similarity, Neu5Gc is handled by the body's biochemical pathways as native. However, the body's immune system recognizes Neu5Gc as foreign and produces antibodies. Therefore, consuming foods containing Neu5Gc may elicit an immune response, triggering inflammation and potentially providing a unique dietary link between the consumption of animal products...

Episodes

Posted on June 9th 2025 (8 days)

Dr. Rhonda Patrick discusses coffee's remarkable ability to slow biological aging, reduce DNA damage, and lower cancer risk.

Posted on January 21st 2025 (5 months)

In this clip, Dr. Rhonda Patrick explores egg consumption, its health impacts, nutrient benefits, cholesterol considerations, and her personal egg preferences.

Posted on December 10th 2024 (6 months)

Dr. Rhonda Patrick discusses _Akkermansia muciniphila_, vitamin B1's effect on blood sugar, emulsifiers in food, and electrolyte supplements.

Topic Pages

  • Caloric restriction

    Caloric restriction, a dietary intervention, reduces energy intake to modulate nutrient-sensing pathways such as mTOR, AMPK, and insulin/IGF signaling.

  • Fasting

    Fasting temporally restricts diet-derived calories, activating AMPK, sirtuin, and ketogenesis pathways distinct from continuous caloric intake.

  • FOXO

    Nutrient deprivation suppresses insulin-PI3K-Akt signaling, dephosphorylating FOXO, enabling nuclear localization that induces autophagy and longevity genes.

  • Microplastics

    Dietary ingestion constitutes a primary exposure pathway whereby microplastics traverse intestinal epithelia and may perturb nutrient absorption.

  • Neu5Gc

    Dietary Neu5Gc from mammalian meat is metabolically incorporated into human glycoconjugates, triggering anti-Neu5Gc antibody–mediated inflammation.

  • Omega-3 fatty acids

    Dietary omega-3 polyunsaturated fatty acids incorporate into membrane phospholipids, shifting eicosanoid synthesis toward less pro-inflammatory mediators.

  • Polyphenols

    Diet supplies polyphenols whose gastrointestinal absorption and hepatic metabolism yield metabolites that modulate redox-sensitive cellular signaling cascades.

  • Salmon roe

    Dietary salmon roe supplies phospholipid-bound EPA/DHA, absorbed by enterocytes, enriching membrane phospholipids and attenuating pro-inflammatory eicosanoid synthesis.

  • Sugar-sweetened beverages (SSBs)

    SSBs in diets provide rapidly absorbed sugars that escape satiety, spike glycemia, stimulate insulin, and augment caloric load.

  • Time-restricted eating

    Diet composition remains constant; time-restricted eating reorganizes feeding windows to synchronize metabolic pathways with circadian rhythms.

News & Publications

  • Seafood provides essential nutrients, but it also raises concerns during pregnancy. Although seafood is high in compounds that promote fetal brain development, worries about mercury levels have frequently shaped recommendations. A recent systematic review found that seafood consumption during pregnancy may enhance a child’s behavioral, social, and cognitive development.

    Researchers reviewed 40 studies (primarily long-term observational research) that tracked seafood consumption during pregnancy and children’s developmental outcomes, including behavior, social-emotional skills, and cognitive abilities. They screened each study for quality and assessed the strength of the evidence based on consistency, effect size, and study design.

    They found that children whose mothers consumed more seafood during pregnancy tended to demonstrate better behavioral and social-emotional development from infancy through adolescence and stronger overall developmental scores before age 4. Some studies linked higher seafood intake to improved attention, reasoning, and verbal intelligence, although findings in those areas were less consistent. The researchers found little to no evidence regarding seafood intake during lactation, and results were mixed for outcomes such as movement, language, attention-deficit/hyperactivity disorder, and autism spectrum disorder.

    These findings suggest that eating seafood during pregnancy—within current recommendations of 8 to 12 ounces per week—supports a child’s development, especially in social and behavioral areas. Learn more about optimizing one’s diet and lifestyle for pregnancy in Aliquot #100: Optimizing for a Healthy Pregnancy & Early Childhood

  • The progression of type 2 diabetes is not inevitable, and early-stage disease can often be reversed. However, standard clinical approaches tend to focus on disease management rather than remission. A recent study found that combining a high-protein diet, moderate exercise, and weight-loss medications promoted diabetes remission in nearly 87% of newly diagnosed people with type 2 diabetes, compared to 17% in those receiving standard care.

    Researchers randomly assigned 61 adults with obesity and either prediabetes or newly diagnosed type 2 diabetes to one of two groups. Both received diabetes medications and general lifestyle advice, but one group also participated in a structured program that combined a high-protein diet with supervised moderate exercise (30 minutes daily, five times a week) for 12 months.

    After a year, 73% of participants with prediabetes in the intensive program returned to normal blood glucose levels, compared to just 8% in the standard care group. Among those with type 2 diabetes, 87% experienced remission in the intensive group, while only 17% did in the standard group. People in the intensive group also lost an average of 19 kilograms (~42 pounds)—roughly 17 kilograms (~38 pounds) more than those in standard care—and showed greater reductions in body fat, liver fat, and visceral fat.

    These findings suggest that when paired with medications (including metformin and GLP1 receptor agonists), an intensive yet manageable lifestyle program can dramatically improve blood glucose and body composition. Learn about Ozempic, a widely used GLP1 receptor agonist, in this episode featuring Dr. Rhonda Patrick.

  • Compounds derived from cruciferous vegetables may influence not only disease prevention but also the fundamental processes of aging. A recent roundworm study found that sulforaphane, a bioactive compound derived from broccoli, extended lifespan by more than 50%, but only when taken early in life.

    Scientists administered varying doses of sulforaphane to roundworms (a robust aging model) throughout different stages of their lives. They also monitored changes in gene activity over time to create an “aging clock” based on transcription patterns—essentially a readout of the worms' biological age determined by which genes were activated or deactivated.

    The worms that received sulforaphane early in life lived considerably longer—more than 50% longer at the most effective dose—than untreated worms. The aging clock also showed that these worms appeared to be about 20% younger, biologically speaking, than untreated worms of the same chronological age. The most notable shifts in gene activity involved detoxification and stress-response pathways, suggesting that sulforaphane triggers system-wide protective responses early in life.

    These findings suggest that sulforaphane could promote healthy aging by activating the body’s natural defense systems, but timing matters, with early-life intervention being crucial. Notably, most human clinical trials use sulforaphane doses ranging from 30 to 100 micromoles daily (approximately 5 to 18 milligrams). These doses are typically delivered as glucoraphanin—the precursor to sulforaphane—paired with myrosinase to enhance conversion in the body. Learn more about sulforaphane in this episode featuring Dr. Jed Fahey.

  • Nitrates from vegetables—especially leafy greens and beets—are generally beneficial, due to their synergistic effects with antioxidants and other protective compounds. In contrast, nitrates in processed meats can form harmful byproducts during cooking or digestion and are linked to higher risks of chronic disease. A recent study found that people who eat more nitrate from vegetables show fewer signs of early brain changes associated with Alzheimer’s.

    Researchers analyzed data from more than 500 cognitively healthy older adults living in Australia. They estimated nitrate intake from food frequency questionnaires. They tracked the participants' brain health over 10 years using two types of brain scans: one to detect beta-amyloid buildup—a hallmark of Alzheimer's—and one to monitor brain shrinkage. They used statistical models to determine whether nitrate intake from different food sources affected brain changes, and whether results differed by sex or by presence of the APOE4 gene variant, which increases Alzheimer’s risk.

    Among women who carried the APOE4 gene variant, those with the highest intake of plant-sourced nitrate accumulated beta-amyloid at about half the rate of those with lower intakes. They also experienced slower shrinkage of the right hippocampus, a region critical for memory. Moderate plant nitrate intake also appeared protective in men with the gene variant and those without it, but the patterns varied depending on sex and genetic risk.

    These findings suggest that nitrate from vegetables helps protect brain health in older adults, particularly those at higher genetic risk for Alzheimer’s disease. The link appeared strongest for markers of beta-amyloid buildup and was less consistent for brain volume loss. Learn about other lifestyle strategies for reducing Alzheimer’s disease risk in this episode featuring Dr. Dale Bredesen.

  • Tomatoes are a rich source of lycopene, a powerful antioxidant that may help protect against cancer and cancer-related death. A recent study found that people with the highest blood levels of lycopene were 11% less likely to develop cancer and 24% less likely to die from it than those with the lowest levels.

    Researchers analyzed data from 121 prospective studies involving more than 100,000 people with cancer and more than 10,000 cancer-related deaths. They focused on studies that reported tomato intake, lycopene levels in the blood, or dietary lycopene consumption and how those related to cancer risk and death.

    Compared with people who had the lowest lycopene levels, those with the highest had an 11% lower risk of developing cancer. High tomato and lycopene intake were each linked to a 5% lower cancer risk. When looking at cancer deaths, people who consumed the most tomatoes were 16% less likely to die from cancer, and those who consumed the most lycopene were 24% less likely. Higher blood levels of lycopene also lowered the risk of dying from lung cancer (the leading cause of cancer deaths) by 35%. In addition, a modest increase in blood lycopene—about 10 micrograms per deciliter—was tied to a 5% drop in overall cancer risk.

    These findings suggest that a diet rich in tomatoes and other lycopene-containing foods could offer modest protection against cancer and may even reduce the risk of dying from it. Lycopene is a carotenoid compound found in tomatoes and watermelon. Learn more about lycopene and other carotenoids in our overview article.

  • Artificial sweeteners like sucralose are marketed as healthier alternatives to sugar, but they may send mixed signals to the brain. A recent study found that sucralose increased hunger and altered activity in the part of the brain that regulates appetite, with effects differing by body weight.

    Researchers asked 75 young adults—some with a healthy weight and some with overweight or obesity—to drink a beverage sweetened with either sucralose (often marketed as Splenda), sucrose (table sugar), or plain water on three separate occasions. Afterward, the researchers measured the participants' blood glucose levels, collected their self-reported hunger ratings, and conducted brain scans to examine activity and connectivity in key regions involved in appetite control.

    Compared to sugar, sucralose increased blood flow to the hypothalamus and promoted stronger feelings of hunger. Sucralose also heightened hypothalamic activity more than water but didn’t influence hunger. Only sugar elevated blood glucose levels, an increase linked to reduced activity in the hunger-regulating regions of the brain.

    Interestingly, the brain’s response to sucralose differed based on body weight: In people with a healthy weight, sucralose enhanced connections between the hypothalamus and areas involved in attention and decision-making. In those with overweight, sucralose diminished connections to brain regions that process bodily sensations. And those with obesity exhibited little to no change in these neural connections. Compared to water, both sweeteners elicited distinct patterns of brain activity depending on weight status.

    These findings suggest that sucralose interferes with the brain’s normal appetite-regulating signals by mimicking sweetness without delivering the expected rise in blood sugar. This mismatch appears to increase hunger and alter brain connectivity in ways that vary depending on body weight. Artificial sweeteners also affect the gut microbiome. Learn more in this clip featuring Dr. Eran Elinav.

  • Glucose has long been considered the brain’s primary fuel, but ketone bodies may offer critical support, especially during periods of low carbohydrate availability. A recent study found that a ketogenic diet boosted levels of brain-derived neurotrophic factor (BDNF)—a key protein that supports brain health—by 47%, highlighting the diet’s potential to support brain health even in people without cognitive impairment.

    Researchers recruited 11 healthy but overweight adults to participate in a randomized, crossover study. Each participant followed two different diets: a ketogenic diet high in fat and low in carbohydrates, and a standard balanced diet. Each diet lasted three weeks and ended with brain imaging scans (using MRI and PET) and blood tests to measure brain blood flow and BDNF levels.

    They found that the ketogenic diet markedly increased ketone levels in the blood compared to the standard diet. Brain blood flow rose by 22% after eating the ketogenic diet, and BDNF levels increased by 47%. Researchers also found a strong link between ketone levels in the blood and higher brain blood flow.

    This was a small study, but the findings suggest that a ketogenic diet enhances brain blood flow and boosts vital brain-supporting proteins, even in people without memory loss. This opens up new possibilities for using ketogenic nutrition as a strategy to preserve cognitive function and support long-term brain health. Learn how to plan the optimal ketogenic diet in this clip featuring Dr. Dominic D'Agostino.

  • Diets that require daily calorie cutting are hard to adhere to, and most people gain the weight back within a year. Intermittent fasting, which involves eating very little on some days and freely on others, might offer a more sustainable alternative. A recent study found that fasting three nonconsecutive days per week promoted more weight loss than daily calorie restriction as part of a comprehensive weight loss program.

    Researchers assigned 165 adults aged 18 to 60 with a body mass index between 27 and 46 to one of two diet plans. One group followed a 4:3 intermittent fasting schedule, eating freely on four days of the week and cutting calories by 80% on three nonconsecutive days each week. The second group followed a daily calorie restriction (about 34% less than baseline needs) to match the same total weekly calorie reduction. Both groups also participated in a year-long behavioral weight loss program that included group support and a goal of 300 minutes of moderate exercise weekly.

    After 12 months, participants in the intermittent fasting group lost roughly 6.4 pounds more, on average, than those in the daily calorie restriction group. Just over three-fourths of participants completed the study. The difference in weight loss between the two groups was small but statistically meaningful.

    These findings suggest that intermittent fasting offers a modest advantage over daily calorie restriction for people trying to lose weight, especially when paired with regular exercise and behavioral support. Learn more about the health benefits of intermittent fasting in this clip featuring Dr. Mark Mattson.

  • With more than 80% of older adults in the U.S. having at least one chronic health condition, finding ways to support healthy aging has become a public health priority. A recent study found that people who followed healthy diets over the long term were more than twice as likely to age well—physically, mentally, and emotionally—even into their mid-70s.

    Researchers followed adults for 30 years as part of two large, long-running health studies in the U.S. They looked at how closely people followed eight well-known dietary patterns, including the Alternative Healthy Eating Index (AHEI)—a scoring system that reflects how well someone’s diet aligns with current nutrition guidelines. Other patterns included the Mediterranean diet, the DASH diet, a plant-based diet, and the Planetary Health Diet.

    The researchers also examined diets linked to higher levels of inflammation and insulin resistance and the amount of ultra-processed food people ate. They then compared these patterns to a comprehensive measure of healthy aging, including physical function, cognitive ability, mental health, and freedom from major chronic disease.

    They found that people with the highest AHEI scores were 2.43 times more likely to maintain good overall health as they aged, up to 75. Similar benefits appeared for people who followed Mediterranean-style, MIND, and plant-based diets. In contrast, those who ate the most ultra-processed food or followed dietary patterns that drive inflammation and high blood glucose levels were less likely to age in good health.

    These findings suggest that long-term dietary choices can meaningfully influence how well we age—not just how long we live. Learn more about lifestyle factors that prolong healthy aging in this episode featuring Dr. Rhonda Patrick.

  • Sleepless nights don’t just leave you tired—they may also interfere with your body’s ability to regulate hunger. Researchers have long known that poor sleep increases the risk of obesity, but the biological link has remained elusive. A recent study found that a sleep-triggered hormone called raptin helps control appetite and may explain why people who don’t get enough sleep are more likely to gain weight.

    Researchers examined brain activity, hormone levels, and eating behavior under different sleep conditions in mice and humans. They identified a previously unknown hormone, which they named raptin, and tracked where and when it was released. They also studied the effects of a genetic variant that blocks raptin production and examined hormone levels in people with sleep deficiency, obesity, and nighttime eating syndrome.

    They discovered that raptin is produced in a part of the brain that regulates hunger and hormone secretion and is released during sleep. When sleep is disrupted, raptin levels drop. In lab experiments, raptin acted on specific receptors in the brain and stomach to reduce appetite and slow stomach emptying. People with obesity and sleep deficiency had lower levels of raptin, while those who underwent therapy to improve sleep showed increases in the hormone. A genetic variant that blocks raptin production was linked to night-time overeating and obesity.

    These findings indicate that raptin explains how sleep influences weight gain and appetite. Learn more about the effects of sleep deprivation in Aliquot #27: Health consequences of sleep deprivation, part I: Metabolic & immune health and Aliquot #28: Health consequences of sleep deprivation, Part 2: Mental & cognitive health

  • Cognitive decline and cardiovascular disease often go hand in hand—and both become more common with age. Nutrition plays a key role in protecting brain and heart health, and certain fruits rich in antioxidants may offer targeted benefits. A recent study found that consuming fresh strawberries daily improved cognitive function and lowered systolic blood pressure by an average of 3% in older adults.

    Researchers provided 35 healthy adults, ages 60 to 78, a strawberry powder or a placebo each day for eight weeks. Each person tried both options in random order, with a four-week break in between. The strawberry powder, made from freeze-dried fruit, delivered the same nutrients and antioxidants as two cups of fresh strawberries. The researchers measured the participants' cognitive function using standard tests and tracked markers of heart health, including blood pressure, waist size, blood lipids, and antioxidant levels.

    The participants' thinking speed improved during the strawberry phase, while episodic memory improved modestly during the placebo phase. After eight weeks of strawberry consumption, systolic blood pressure dropped by an average of 3%, and waist size decreased slightly. Participants' blood antioxidant capacity increased with strawberries but decreased with the placebo. Triglycerides increased during the placebo period but remained stable with strawberries.

    The findings from this small study suggest that regular strawberry intake supports brain and heart health in older adults. Strawberries are rich in polyphenols. Learn more about polyphenols in our overview article.

  • Sugar-sweetened beverages contribute to weight gain and increase the risk of severe health concerns, such as type 2 diabetes and cardiovascular disease. A recent study revealed that in 2020, sugar-sweetened drinks were linked to 2.2 million new cases of type 2 diabetes and 1.2 million new cases of cardiovascular disease globally.

    Researchers utilized the Global Dietary Database to assess the global, regional, and national effects of type 2 diabetes and cardiovascular disease associated with sugar-sweetened beverage consumption in 184 countries, comparing data from 1990 to 2020. They also considered factors such as age, sex, education, and whether people lived in urban or rural areas to provide further context for the findings.

    They found that sugar-sweetened beverages were associated with 9.8% of new type 2 diabetes cases and 3.1% of new cardiovascular disease cases in 2020. The burden was greatest in Latin America and the Caribbean, where sugar-sweetened beverages accounted for 24.4% of type 2 diabetes cases and 11.3% of cardiovascular disease cases. Sub-Saharan Africa also experienced a marked increase in type 2 diabetes and cardiovascular disease related to sugar-sweetened beverages over the past three decades.

    These findings suggest that sugar-sweetened beverages have deleterious effects on human health and underscore the need for targeted interventions to reduce their consumption. Learn more about sugar-sweetened beverages in our overview article.

  • Study link:

    Indulging in a junk food binge can have lasting effects on your brain, even after you return to your usual eating habits. A recent study found that five days of overeating high-calorie, nutrient-poor foods temporarily boosted brain insulin sensitivity but caused a drop in responsiveness once participants switched back to a healthier diet.

    Researchers assigned 29 healthy-weight men, ages 19 to 27, to one of two groups: One followed a junk food diet for five days, while the other stuck to their regular eating habits. They measured participants' brain insulin activity through imaging techniques and insulin administration before and after the binge.

    At the peak of the junk food binge, researchers observed heightened insulin activity in key brain regions. However, just one week after returning to their usual diet, participants who had overindulged experienced lower brain insulin sensitivity, particularly in areas associated with memory and food-related reward, such as the hippocampus and fusiform gyrus. Interestingly, while the junk food group showed increased liver fat, there were no noticeable changes in weight or peripheral insulin sensitivity.

    These findings suggest that the effects of overeating go beyond immediate metabolic changes, potentially contributing to cognitive decline and influencing eating behaviors over time. They also underscore how even a brief junk food binge can disrupt insulin function in the brain, impairing areas critical to memory and decision-making. Behavioral strategies like mindfulness can help curb overeating. Learn more in this clip featuring Dr. Ashley Mason.

  • Many people with prediabetes never receive structured treatment, even though early intervention offers the best chance of reversing high blood sugar. While lifestyle changes are the primary recommendation, they are challenging to implement and often ineffective. A recent study found that a broccoli sprout extract rich in sulforaphane modestly lowered fasting blood sugar in some people with prediabetes.

    Researchers conducted a 12-week, randomized, double-blind, placebo-controlled trial involving 74 participants with prediabetes who had not previously taken medication for the condition. Participants took a daily dose of broccoli sprout extract or a placebo, and researchers measured changes in their fasting blood sugar. They also analyzed gut microbial composition and genetic markers to explore potential differences in response.

    Overall, the extract slightly reduced fasting blood sugar levels (3.6 milligrams per deciliter, mg/dL) compared to the placebo but did not meet the predefined target for effectiveness. However, a subgroup of participants with mild obesity, lower insulin resistance, and reduced insulin secretion saw a greater reduction in blood sugar—about 7.2 mg/dL. These participants also had a distinct gut microbiota composition, including a higher abundance of bacterial genes linked to sulforaphane activation.

    Sulforaphane forms when glucoraphanin, found in broccoli sprouts, interacts with the enzyme myrosinase. Myrosinase activates when the plant cells are damaged, such as during chewing or processing. In the absence of myrosinase, some people’s gut microbes produce similar enzymes, helping convert more glucoraphanin into sulforaphane. This variation in gut bacteria may explain why some people respond more strongly to sulforaphane-rich foods or supplements.

    These findings suggest that gut microbes and individual metabolic traits may influence the effectiveness of nutritional interventions for prediabetes. One in three people in the U.S. has prediabetes. Learn more in this clip featuring Dr. Michael Snyder.

  • Scientists have long debated whether artificial sweeteners influence insulin levels and cardiovascular risk. A recent study found that consuming aspartame, a popular artificial sweetener, sharply increased insulin secretion in mice and monkeys, a process driven by parasympathetic nervous system activation.

    Researchers fed mice a diet containing 0.15% aspartame and measured changes in blood insulin levels. They also surgically severed the vagus nerve in some animals to assess whether parasympathetic activation was involved. To examine insulin’s role in atherosclerosis, they implanted slow-release insulin pumps in mice to mimic chronically elevated insulin levels. Finally, they tested aspartame’s effects in Cynomolgus monkeys, which are metabolically similar to humans.

    They found that mice that consumed aspartame experienced a sharp increase in insulin secretion, an effect eliminated after severing the vagus nerve. Long-term aspartame consumption worsened atherosclerosis, and implanting insulin pumps had a similar effect. In monkeys, aspartame triggered an insulin spike comparable to the effects of sucrose. However, instead of raising blood sugar, it lowered it, potentially driving insulin resistance, inflammation, and increased risk of atherosclerosis. Further analysis revealed that aspartame-induced insulin secretion activated cell signaling pathways linked to arterial inflammation and plaque formation.

    These findings suggest that aspartame consumption worsens cardiovascular risk by increasing insulin secretion, altering glucose metabolism, and promoting inflammation and plaque buildup in the arteries. Notably, the aspartame dose used in the experiment greatly exceeds what most humans consume. While the study provides insight into biological effects, its relevance to typical human intake is unclear due to the high exposure levels. Learn more about artificial sweeteners and other sugar substitutes in Aliquot #66: Sugar substitutes: Risks and benefits

  • Many people eat without thinking while watching TV, scrolling on their phones, or working on a computer. This habit is more than just a distraction—it can influence how much people eat and what types of foods they choose. A recent study found that screen use increases food intake, especially among women, regardless of what’s on the screen.

    Researchers conducted a systematic review and meta-analysis, analyzing data from 23 experimental studies involving nearly 1,900 participants. They compared food intake between those who watched screens while eating and those who did not, as well as among groups exposed to different types of screen content, such as food-related images or weight-control messages.

    They found that watching a screen while eating increased food consumption, particularly among women. Screen content modestly influenced intake, and duration mattered. For example, food cues slightly increased intake when screen time was under 30 minutes. However, when exposure lasted longer, food intake remained elevated regardless of the content, suggesting prolonged screen use drives overeating.

    These findings suggest that simply having a screen on during meals may encourage overeating, no matter what’s being watched. Reducing screen exposure during meals could be a simple way to help regulate food intake and support healthier eating habits. Learn about the effects of screen time on kids in this episode featuring Dr. Rhonda Patrick.

  • Gray hair is often considered an inevitable part of aging, but evidence suggests lifestyle strategies—including diet—could slow it down. A recent study in mice found that luteolin, a plant-derived antioxidant, may help prevent hair graying by targeting key cellular processes.

    Researchers tested the effects of three antioxidants—luteolin, hesperetin, and diosmetin—on hair graying in mice prone to premature graying. They applied the compounds topically and administered them orally, then analyzed changes in hair color, stem cell activity, and molecular markers associated with aging hair follicles.

    Luteolin, but not the other antioxidants, substantially reduced hair graying in the mice. Both topical and oral luteolin helped maintain communication between hair follicle stem cells and melanocyte stem cells,which are essential for pigment production. Mice treated with luteolin also had fewer aging-related changes in these cells, suggesting it protects against age-related hair follicle dysfunction.

    These findings suggest that luteolin is a promising candidate for an anti-graying treatment. Luteolin is abundant in celery, green pepper, broccoli, carrots, and olive oil, and is also available as a dietary supplement. Learn about other strategies to slow or prevent hair graying in this episode featuring Dr. Rhonda Patrick.

  • Anxiety disorders affect millions of adults each year, and emerging evidence suggests that diet influences symptoms. Oxidative stress likely contributes to anxiety, but antioxidants may help counteract its effects. A recent study found that people with severe anxiety consumed fewer antioxidants than those without anxiety and that increasing antioxidant intake substantially reduced anxiety symptoms.

    Researchers first compared the daily antioxidant intake of adults with and without severe anxiety. Then, they carried out an interventional study, providing 40 adults with severe anxiety with an antioxidant-rich beverage daily for six weeks to assess changes in anxiety levels. The beverage contained 15 grams of green tea (containing polyphenols and tannins), 3 grams of cinnamon powder (containing cinnamaldehyde and proanthocyanidins), and three lemon slices (containing flavonoids and vitamin C).

    They found that people with severe anxiety had considerably lower daily antioxidant intake than those without. However, after six weeks of higher antioxidant intake, participants experienced a substantial reduction in their anxiety levels.

    This was a small study, but its findings suggest that dietary antioxidants play a role in managing anxiety, potentially offering a simple, nutrition-based lifestyle approach to reducing anxiety symptoms. Learn about other lifestyle strategies for managing anxiety in Aliquot #8: Lifestyle interventions for depression and anxiety.

  • Anthocyanins, the compounds that give berries their deep red and purple hues, may do more than add color to a meal. Evidence suggests these potent antioxidants protect brain health, particularly in people at higher risk of dementia. A recent study found that anthocyanins improved cognitive function in people with high inflammation levels, but not those with lower inflammation.

    Researchers conducted a 24-week randomized, placebo-controlled trial to examine anthocyanins' effects on cognition. They categorized participants into two groups based on inflammation levels, using blood biomarkers to make the distinction. Each participant received either anthocyanins or a placebo, and the researchers measured cognitive function before and after the intervention.

    The cognitive test results indicated that participants with high inflammation experienced marked cognitive improvements after anthocyanin treatment, while those with lower inflammation saw no benefit. Interestingly, participants in the high-inflammation group had higher body mass indexes, greater diabetes prevalence, and lower HDL (“good”) cholesterol levels.

    These findings suggest that anthocyanins improve cognitive function among people with high inflammation. Anthocyanins are polyphenolic compounds. Learn more about polyphenols in our overview article.

  • Strict vegetarian diets are gaining popularity, but concerns remain about their safety during pregnancy. A recent study found that pregnant women following strict vegetarian diets are 2.7 times more likely to have a small-for-gestational-age infant, with their newborns weighing an average of 240 grams (about half a pound) less at birth.

    Researchers conducted a systematic review and meta-analysis of eight studies involving more than 72,000 participants. They examined key pregnancy outcomes, including birth weight, the risk of small-for-gestational-age infants, gestational diabetes, hypertensive disorders, and gestational weight gain.

    They found that pregnant women adhering to strict vegetarian diets were 2.7 times more likely to have a small-for-gestational-age infant compared to those consuming animal products. Their infants also weighed, on average, 240 grams (approximately half a pound) less at birth. While strict vegetarian diets were linked to lower gestational weight gain, they did not affect the risk of gestational diabetes or hypertensive disorders.

    These findings suggest that without careful planning, strict vegetarian diets during pregnancy increase the risk of inadequate fetal growth. Ensuring sufficient intake of essential nutrients—such as vitamin B12, iron, omega-3 fatty acids, and iodine—through supplementation or fortified foods could help reduce this risk. Learn more about how to have a healthy pregnancy in Aliquot #100: Optimizing for a Healthy Pregnancy & Early Childhood.

  • Aging impairs mitochondrial function, disrupting the heart’s energy supply. Over time, this energy shortfall undermines cardiac cell function, driving the heart’s gradual decline. A recent study found that supplemental urolithin A—a bioactive compound derived from pomegranates and walnuts—boosts mitochondrial health and reduces pro-inflammatory lipids called ceramides, ultimately enhancing cardiac function.

    Researchers investigated the effects of supplemental urolithin A in models of natural aging in mice and heart failure in rats and assessed its effects on plasma ceramide levels in healthy older adults. Mice received 50 milligrams per kilogram of urolithin A daily (in food) for eight weeks, rats received 50 milligrams per milliliter (in water) for 24 hours following a simulated heart attack, and the older adults took 1 gram of urolithin A (via supplement) or a placebo daily for two to four months.

    Supplemental urolithin A improved systolic and diastolic cardiac function in models of natural aging and heart failure—an effect of the restoration of mitochondrial structure and enhanced mitophagy at the cellular level. Four months of urolithin A supplementation in healthy older adults significantly lowered plasma ceramides.

    Ceramides are a class of bioactive lipids that contribute to cardiovascular disease by promoting inflammation, insulin resistance, and lipid accumulation in arteries. Elevated ceramide levels are linked to a higher risk of atherosclerosis and adverse cardiac events.

    Urolithin A is a byproduct of gut microbial metabolism of ellagic acid, a bioactive compound found in pomegranates and walnuts. The capacity to form urolithin A from ellagic acid varies considerably from person to person (depending on gut microbial composition) and decreases with age. Pterostilbene, a compound found in blueberries and some supplements, boosts urolithin A conversion. Learn more in this clip featuring Dr. Rhonda Patrick.

  • Roughly 60% of the human brain is made up of fat, which plays a crucial role in the structure and function of brain cells. In Alzheimer’s, fat metabolism in the brain becomes altered, influencing disease progression. A recent study found that a modified Mediterranean ketogenic diet boosted healthy fats in the brain and lowered Alzheimer’s-associated markers.

    The study included 20 adults with prediabetes who were at risk for developing Alzheimer’s. Participants followed the modified Mediterranean ketogenic diet or the American Heart Association diet for six weeks. After a six-week break, they switched to the opposite diet for another six weeks. Before and after each diet intervention, participants underwent cognitive testing, and the researchers evaluated their blood lipids and Alzheimer’s markers, including amyloid-beta and tau.

    They found that the modified Mediterranean ketogenic diet caused notable changes in blood lipids, increasing molecules linked to fat breakdown and energy use (such as free fatty acids and acylcarnitines) while lowering triglycerides. It also boosted healthy lipid types (plasmalogens) and reduced harmful ones (deoxyceramides). These alterations in blood lipids correlated with improved Alzheimer’s biomarkers and cognitive measures. The American Heart Association diet had little or no effect on blood lipids or cognitive function.

    The traditional ketogenic diet is high in fat and low in carbohydrates. The modified Mediterranean-ketogenic diet is rich in fish, lean meats, and fiber-rich green leafy vegetables, nuts, and berries. About 5% to 10% of its calories come from carbohydrates, 60% to 65% from fat, and 30% from protein. In the American Heart Association diet, about 55% to 65% of calories come from carbohydrates, 15% to 20% from fat, and 20% to 30% from protein.

    The findings from this small intervention study suggest that a modified Mediterranean ketogenic diet protects against Alzheimer’s disease. Learn more about the ketogenic diet and Alzheimer’s disease in this clip featuring Dr. Dale Bredesen.

  • Fat is a vital energy source, but when consumed in excess, it can promote obesity. However, the amount of fat the body absorbs may be more related to the brain than the gut. A recent study in mice found that signals from the brain’s vagus nerve regulate fat uptake in the intestine, offering a potential means to moderate obesity.

    Researchers manipulated the dorsal motor nucleus of the vagus (DMV), which plays a crucial role in digestion. They inactivated DMV neurons that connect to the jejunum (the middle portion of the intestine), shortening the length of the microvilli in the gut and reducing fat absorption. However, stimulating DMV neurons increased fat absorption and promoted weight gain. Finally, they injected mice with puerarin, a bioactive compound derived from the kudzu plant, and found that the compound mimicked the effect of DMV suppression, further reducing fat absorption.

    These findings suggest that controlling the DMV-vagus-jejunum pathway could provide a novel approach to managing fat absorption and weight. They also highlight yet another way the brain-gut axis influences human health.

    Puerarin is an isothiocyanate, a class of sulfur-containing compounds known for their potent anti-inflammatory, anti-cancer, and anti-obesity effects. Sulforaphane, another well-known isothiocyanate, shares many of these beneficial properties. To learn more about the health effects of sulforaphane, check out our overview article.

  • Although iron is essential for many physiological processes in the body, it can also be harmful, inducing oxidative stress and hindering neurogenesis. The body typically stores iron in protein complexes until needed, but these storage processes decline with age, leading to iron accumulation in body tissues. A recent study revealed that iron can build up in the brain, impairing cognitive function. Nevertheless, dietary components can help reduce iron accumulation in the brain and maintain cognitive health.

    Researchers examined the brain health of 72 cognitively healthy older adults by conducting brain scans at baseline and two to three years later. Participants provided details about their dietary habits, physical activity, and overall health. They also underwent cognitive tests that evaluated their episodic memory and executive function.

    The brain scans revealed that iron levels increased markedly over time, and higher iron accumulation correlated with poorer cognitive function. However, a higher intake of antioxidants, vitamins, iron-chelating nutrients, and polyunsaturated fatty acids mitigated iron accumulation. Iron-chelating nutrients include polyphenolic compounds, such as gallic acid and catechins (in tea), caffeic acid (in coffee), quercetin (in apples and onions), ellagic acid (in walnuts and pomegranates), curcumin (in turmeric) and others.

    These findings suggest that diet mitigates iron accumulation in the brain, ultimately influencing cognitive health. Interestingly, alcohol can promote iron accumulation in the brain. Learn more in this episode featuring Dr. Rhonda Patrick.

  • It’s no surprise that sugar-sweetened drinks can contribute to weight gain, dental problems, and metabolic impairments. But emerging evidence suggests they can also harm your heart. A recent study found that consuming more than eight sugar-sweetened drinks weekly increases the risk of various cardiovascular diseases by as much as 31%.

    Researchers investigated links between sugar intake and cardiovascular disease among nearly 70,000 people. They asked participants about their sugar intake from various sugar-sweetened foods and drinks. Then, using national disease registers, they ascertained the incidence of various cardiovascular diseases, including ischemic and hemorrhagic stroke, myocardial infarction (heart attack), heart failure, aortic stenosis (narrowing of the aorta), atrial fibrillation (abnormal heart rhythm), and abdominal aortic aneurysm (ballooning of the major blood vessel in the abdomen).

    They found that the risk of developing cardiovascular disease varied according to disease type and sugar source. However, drinking more than eight sugar-sweetened beverages weekly carried the greatest risk, increasing a person’s chances of ischemic stroke by 19%, heart failure by 18%, atrial fibrillation by 11%, and abdominal aortic aneurysms by 31%.

    The investigators posited that sugar in beverages is readily metabolized, increasing its potential for harm. Learn more about the health effects of sugar-sweetened beverages in our overview article.

  • Breakfast is often touted as the most important meal of the day. But for teenagers, the composition of that breakfast may be more critical than previously thought. A recent study found that eating a high-protein breakfast increases gene expression associated with cardiovascular health, potentially protecting teens against heart disease later in life.

    The study included 30 teens who routinely skipped breakfast. For six months, 10 of the teens ate a normal-protein breakfast (10 grams of protein) daily, 10 ate a high-protein breakfast (30 grams of protein), and 10 continued skipping breakfast. The normal-protein and high-protein breakfasts both provided 350 calories. Researchers measured the teens' levels of microRNAs (small, non-coding RNA molecules that regulate gene expression) associated with higher cardiovascular disease risk.

    They found no difference in miRNA levels among the three groups. However, they observed a significant pattern over time for one microRNA—miR-126-3p—which increased more in those eating high-protein breakfasts than those who skipped breakfast. miR-126-3p regulates angiogenesis (the formation of new blood vessels) and helps maintain blood vessel integrity. It also reduces inflammation—a driver of cardiovascular disease.

    This small study suggests that eating a high-protein breakfast can have lasting effects on teens who regularly skip breakfast, potentially reducing their risk of cardiovascular disease later in life. Skipping breakfast coupled with late-night eating can have harmful effects on metabolic health, too. Learn more in this clip featuring Dr. Ruth Patterson.

  • Flaxseed oil is rich in alpha-linolenic acid (ALA), an omega-3 fatty acid. In the liver, ALA converts to docosahexaenoic acid (DHA), a crucial component of brain health. Evidence suggests that low DHA levels can impair cognitive function. However, a recent study in older adults found that supplemental flaxseed oil enhances cognitive function, particularly verbal fluency—the ability to retrieve and use words quickly.

    The study involved 60 cognitively healthy older adults between the ages of 65 and 80. Half of the participants received 3.7 grams of flaxseed oil containing 2.2 grams of ALA daily for 12 weeks, and the other half received corn oil. Before and after the intervention, researchers assessed aspects of their cognitive function, including verbal fluency.

    Verbal fluency relies on several cognitive skills, including recalling word meanings, finding the right words quickly, processing information efficiently, controlling impulses, holding and using information in the moment, switching between tasks or ideas, and adapting to new situations. It also involves multiple areas of the brain working together. Unfortunately, verbal fluency declines with age, impairing conversation and social interactions and serving as a predictor of Alzheimer’s disease.

    The researchers found that participants who received the ALA-rich flaxseed oil supplement had higher verbal fluency than their peers who received the corn oil, suggesting that flaxseed oil is suitable for delivering crucial omega-3s to the brain. Learn more about the effects of omega-3s on brain health in this clip featuring Dr. Axel Montagne.

  • The primary contributor to cardiovascular disease risk is simply age. Our blood vessels become thicker and less flexible as we get older, rendering them less efficient. However, a recent study found that creatine supplementation restores aspects of cardiovascular function, including blood vessel flexibility and efficiency, in older adults.

    Researchers conducted a small pilot study involving 12 sedentary but healthy older adults. Half of the participants consumed 20 grams of creatine monohydrate daily for five days, followed by 5 grams daily for 23 days. The other half consumed a placebo for 28 days. The researchers measured aspects of the participants' cardiovascular health, including flow-mediated dilation (how flexible a blood vessel is), microvascular perfusion rates (how quickly and efficiently tiny blood vessels fill), blood glucose levels, and triglycerides.

    They found that participants who consumed creatine experienced small but meaningful improvements in their cardiovascular markers, including increased flow-mediated dilation, improved microvascular perfusion rates, and decreased blood glucose and triglycerides. Those who consumed the placebo did not experience these beneficial effects, suggesting that creatine restored their cardiovascular function.

    Creatine is a nitrogen-containing compound that plays an essential role in the recycling of ATP. It is widely used as a dietary supplement to build and maintain muscle mass. Although creatine is available in many forms, most of the research on the compound has focused on creatine monohydrate. Learn more about creatine in this clip featuring Dr. Stuart Phillips.

  • Protein misfolding in the brain is a central player in both aging and Alzheimer’s disease, driving toxic protein buildup and brain cell dysfunction. However, evidence indicates that ketones—a critical brain fuel produced during fasting or exercise—may help reduce or prevent this damage. A recent cell study found that beta-hydroxybutyrate, a type of ketone, helps protect the brain by targeting toxic proteins for disposal.

    Researchers delivered beta-hydroxybutyrate to brain cells collected from mice and monkeys via an exogenous ketone ester. They examined the cells for changes in protein solubility and pathways involved in protein breakdown. They also studied beta-hydroxybutyrate’s effects on pathological proteins, such as amyloid-beta, in a nematode model of Alzheimer’s disease.

    They found that beta-hydroxybutyrate made pathological proteins insoluble, preventing their toxic spread while promoting their clearance through autophagy, the cell’s natural recycling process. This effect was specific to pathological proteins and wasn’t the result of changes in acidity or random chemical interactions. Beta-hydroxybutyrate also reduced amyloid-beta toxicity in nematodes.

    These findings suggest that a ketone ester of beta-hydroxybutyrate counteracts the toxic buildup of proteins in aging and Alzheimer’s disease. Further research is needed to translate these results to humans. Learn more about how ketone ester supplementation may improve brain health in this episode featuring Dr. Mark Mattson.

  • Stress damages the heart and blood vessels, increasing the risk of cardiovascular events like heart attack or stroke. Stress can also drive people to make poor dietary choices, often leading to overeating or consuming high-fat, low-nutrient foods instead of healthier options like fruits and vegetables. A recent study found that cocoa flavanols help counteract the harmful effects of stress and unhealthy meals on the heart and blood vessels.

    The study involved 23 healthy young adults. Each participant ate a high-fat meal (buttered croissants, cheese, and whole milk) paired with either a high-flavanol cocoa drink or a low-flavanol cocoa drink before completing an eight-minute stress task. Researchers measured their blood vessel function, brain oxygen levels, blood flow, blood pressure, and mood multiple times before and after the stress challenge.

    Participants who drank the high-flavanol cocoa maintained better blood vessel function after stress than those who consumed the low-flavanol drink. Blood vessel function declined considerably within 30 minutes of the stress task in the low-flavanol group but was preserved with high flavanol intake. At 90 minutes, blood vessel function improved beyond pre-stress levels in the high-flavanol group. The two groups had similar stress-related changes in blood pressure, brain oxygenation, and mood.

    The findings from this small study suggest that flavanol-rich foods help protect the cardiovascular system during stressful periods, even when accompanied by unhealthy meals. Flavanols are polyphenolic compounds in dark chocolate, berries, apples, and tea. Evidence suggests flavanols exert potent antioxidant and anti-inflammatory properties. Learn more about flavanols and other polyphenols in our overview article.

  • Proteins in milk, meat, and other foods can trigger allergic reactions in some people. However, these proteins—called antigens—can also interact with the immune system to suppress small intestinal tumors. A recent study in mice found that food antigens help activate immune responses in the small intestine, potentially reducing the risk of tumors.

    Researchers fed mice genetically prone to developing intestinal tumors—similar to the genetic predisposition to familial adenomatous polyposis in humans—an antigen-free diet to pinpoint the role of food components in immune activation. They also depleted immune tissues in the animals' small intestines called Peyer’s patches to investigate how food antigens trigger immune cells.

    They found that food antigens activate immune cells in Peyer’s patches, suppressing small intestinal tumor formation. This immune response is crucial for maintaining a tumor-suppressive environment in the gut.

    These findings suggest that food antigens help protect against small intestinal tumors in mice by activating immune cells that promote tumor suppression, highlighting their potential as a protective factor in gut health. The microbiome plays a key role in gut health, too. Learn more in this episode featuring Dr. Eran Elinav.

  • Eggs are a dietary paradox: high in cholesterol but rich in brain-boosting nutrients, including choline, lutein, and zeaxanthin. While some studies indicate that eggs maintain cognitive health, others report the converse. A recent study found that eating eggs may help women preserve semantic memory—crucial for language comprehension and factual recall—as they age.

    Researchers analyzed data from 890 adults aged 55 and older. Participants reported their egg consumption using a food frequency questionnaire, and researchers measured their memory and thinking skills at two clinic visits about four years apart.

    They found that women who ate five eggs weekly experienced less decline in verbal fluency, a measure of semantic memory, than those who ate fewer eggs. In men, researchers found no clear relationship between egg intake and changes in cognitive performance. Eating eggs did not appear to harm cognitive function in either sex.

    These findings suggest that eggs play a small but beneficial role in preserving memory in women. They also align with other research demonstrating that people with moderate choline intake—roughly the amount in two eggs—are about half as likely to have low cognitive function than those with the lowest intake.

  • Brain atrophy occurs naturally with aging, but certain factors such as type 2 diabetes, high blood pressure, and inflammation can accelerate this process, increasing the risk of cognitive decline. However, eating a healthy diet may help slow brain aging. A recent study found that two versions of the Mediterranean diet reduced markers of brain atrophy by 50% over 18 months compared to general healthy eating guidelines.

    Researchers assigned participants aged 50 or older with abdominal obesity or abnormal blood lipids to one of three diets: one that followed standard healthy dietary guidelines, a calorie-restricted Mediterranean diet (which included walnuts and olive oil and substituted chicken and fish for lamb and beef), or a “green” calorie-restricted Mediterranean diet enriched with polyphenols from green tea and mankai, an aquatic plant. The participants underwent brain imaging to assess hippocampal atrophy, a key marker of brain aging, and the researchers tracked changes in body weight, blood sugar, and inflammation over the study period.

    Participants following the green Mediterranean diet showed the greatest preservation of brain volume, particularly in the hippocampus. They also experienced improvements in HbA1c (a marker of long-term blood glucose control), insulin resistance, fasting glucose, and C-reactive protein. Improvements in blood sugar levels and inflammation were closely linked to better brain health outcomes, and greater intake of polyphenol-rich foods like mankai and green tea further enhanced these benefits.

    Mankai, also called duckweed, is rich in polyphenols, omega-3 fatty acids, dietary fiber, and many micronutrients, including iron and vitamin B12. The polyphenols in mankai exert robust antioxidant activity and support healthy blood glucose levels—critical elements in maintaining brain health.

    These findings suggest that diets rich in polyphenols and designed to improve metabolic health may help protect against age-related brain atrophy and keep the brain biologically younger. Learn more about the health benefits of polyphenols in our overview article.

  • The global obesity epidemic is driving a marked increase in the incidence of type 2 diabetes, and some experts estimate that by 2024, more than 780 million adults worldwide will develop the disease. A recent study found that high-protein, low-calorie diets promote weight loss and improve cardiometabolic markers in people at risk for type 2 diabetes.

    The study involved 117 adults with either prediabetes or type 2 diabetes and a body mass index (BMI) over 27.5—considered overweight or obese. Participants consumed an animal- or plant-based high-protein diet that provided 35% of their total calories for six months. The remainder of their calories came from fat (30%) and carbohydrates (35%).

    Participants in both groups saw similar improvements in body composition, including an average weight loss of approximately 8 kilograms (~18 pounds) and reduced visceral (abdominal) fat. Glucose metabolism indicators, such as fasting glucose and glycated hemoglobin levels, improved equally in both groups, as did lipid levels, liver enzymes, and inflammatory markers.

    These findings suggest that high-protein, low-calorie diets—whether animal- or plant-based—can improve body composition, glucose metabolism, and other cardiometabolic markers in people with prediabetes or type 2 diabetes.

    Dietary protein supports muscle hypertrophy and maintenance—critical aspects of glucose metabolism. Learn how to optimize protein intake to support muscle health when following a plant-based diet in this clip featuring Dr. Luc van Loon.

  • With millions worldwide affected by obesity-linked conditions like diabetes and cardiovascular disease, understanding which dietary methods are most effective has become crucial. A recent review and meta-analysis found that fasting-based strategies are slightly more effective for promoting weight loss and improving insulin sensitivity than calorie restriction.

    Researchers reviewed 10 randomized controlled trials involving more than 600 participants to compare the effects of fasting-based and calorie-restricted diets on weight loss and metabolic health. Fasting-based strategies included intermittent fasting, time-restricted eating, and alternate-day fasting, while continuous calorie restriction involved reducing daily caloric intake by 20% to 40% without meal timing changes.

    They found that both methods effectively reduced body weight, with participants losing around 5.5 to 6.5 kilograms (roughly 12 to 14 pounds) after six months. Fasting-based approaches had a slight edge in short-term weight and fat loss—about 1 kilogram (2.2 pounds) more than calorie restriction—but both approaches had similar effects on lean body mass, waist and hip circumference, blood pressure, lipid levels, and glucose metabolism. Notably, fasting-based methods also lowered fasting insulin levels and improved insulin sensitivity.

    These findings suggest that while both methods support weight loss, fasting-based diets may offer additional short-term metabolic benefits. Learn more about fasting-based diets and calorie restriction from these great resources:

    What type of fasting is best? Caloric restriction vs. periodic fasting and the importance of re-feeding after a fast The link between sirtuins, calorie restriction, fasting, and the insulin pathway Topic article: Fasting

  • Cognitive decline is a growing concern as populations age, and diet may play a key role in preserving cognitive function. A 2021 study found that people with moderate choline intake—about the amount in two to three eggs or a serving of salmon—were half as likely to experience cognitive decline than those with low intake.

    Researchers categorized roughly 2,400 older adults enrolled in NHANES based on their daily choline intake: low (less than 188 milligrams), moderate (188 to 400 milligrams), or high (more than 400 milligrams). Then, they ranked them according to their performance on various cognitive tests.

    They found that people with moderate choline intake were 33% to 50% less likely to have low cognitive function than those with the lowest intake. Interestingly, those with higher intake didn’t perform better on the cognitive tests, suggesting a “sweet spot” for choline intake.

    These findings indicate that incorporating moderate amounts of choline-rich foods into one’s diet may protect brain health during aging. This protective effect may be due to choline’s role in producing acetylcholine, a neurotransmitter involved in neurogenesis, synapse formation, learning, and memory. In addition, research in animal models shows that choline deficiency increases the risk of Alzheimer’s disease and damages vital organs in mice.

    Choline is found in many foods. Good sources of this essential nutrient include: - Eggs (1 large): ~147 milligrams - Fish (salmon, 3 ounces, cooked): ~187 milligrams - Cauliflower (1 cup, cooked): ~72 milligrams - Beef (3 ounces, cooked): ~78 milligrams Learn more about choline’s role in brain health in this Q&A featuring Dr. Rhonda Patrick.

  • If drinking a nice, cold soda sounds appealing, you’re not alone. Roughly half of all adults and nearly two-thirds of kids in the US consume at least one soft drink daily—mostly sodas. These drinks typically contain considerable amounts of sugar, raising concerns about their effects on dental and metabolic health. However, a recent study has uncovered a more alarming issue: Microplastic contamination is pervasive in these popular beverages.

    Researchers analyzed the microplastic content in a popular soda brand purchased in various US locations: Atlanta, Los Angeles, Chicago, and Washington, DC. The sodas were in aluminum, glass, or plastic containers.

    They found that the average concentration of microplastic particles in 100 milliliters of soda was 166, with some samples reaching a staggering 482 particles—meaning that a typical 16.9-ounce (~500-milliliter) bottle of soda could contain more than 2,400 microplastic particles. Interestingly, the sodas in glass containers had the highest concentrations of particles. The study investigators speculated that the primary contributors to the sodas' microplastic contamination were local water sources (near the packaging plants).

    These findings suggest that microplastic contamination in sodas is ubiquitous and adds to the growing body of evidence about microplastics in food and beverages. Learn more about microplastics in our overview article.

  • What we eat and drink can profoundly affect our disease risk as we age. A recent study found that consuming just 1.5 teaspoons of olive oil daily can reduce the risk of death from dementia by 28%, even among APOE4 carriers, a potent genetic risk factor for dementia.

    Researchers asked more than 92,000 healthy, middle-aged adults about their olive oil consumption over a 28-year period. They conducted genetic analyses to determine whether the participants carried the APOE4 gene. Then, using national death records, they ascertained which of the participants died of dementia.

    They found that more than 4,700 of the participants died of dementia during the study period. People who carried one APOE4 allele were roughly twice as likely to die from dementia; those with two APOE4 alleles were five to nine times more likely. However, people who consumed 7 grams or more of olive oil daily—roughly 1.5 teaspoons—were 28% less likely to die of dementia than those who didn’t consume olive oil, regardless of their APOE4 status. Replacing 5 grams (about a teaspoon) of margarine or mayonnaise with an equivalent amount of olive oil reduced the risk of death from dementia by as much as 14%.

    These findings suggest that eating olive oil markedly reduces the risk of death from dementia. Olive oil contains healthy fats and polyphenols—bioactive compounds with potent antioxidant and anti-inflammatory properties. Learn more about polyphenols in our overview article.

  • Genes play critical roles in determining how long a person lives, but a new study suggests that the secret to longevity may be as simple as “food as medicine.” Centenarians—people who live 100 years or more—typically eat healthy, balanced diets and require fewer medications than their shorter-lived peers.

    Researchers analyzed studies examining the lifestyles, medication use, and overall health of centenarians and near-centenarians aged 95 to 118. Their analysis included 34 studies and involved more than 59,000 participants.

    They identified several healthy lifestyle habits of long-lived adults: Engaging in regular physical activity Avoiding alcohol and tobacco Adhering to a diverse, macronutrient-balanced diet Preferring less salty foods Using few medications—with just over four taken daily, primarily blood pressure medicines or other cardiovascular drugs

    Multiple drug use—known as polypharmacy—is common in older adults. Defined as taking more than five medications daily, polypharmacy is linked with many adverse health effects, especially among older adults, who are at risk of a “prescription cascade”—where the side effects of drugs can be misdiagnosed as symptoms of another disease, creating a vicious cycle of more drug use.

    This analysis suggests that using food as medicine—through healthy, balanced diets—combined with lower drug use contributes to healthy aging and longevity. Learn how other healthy lifestyle behaviors like exercise and dietary supplementation also promote longevity in this episode featuring Dr. Rhonda Patrick.

  • Although a person’s genes play a pivotal role in whether they develop diabetes, lifestyle factors—like diet, exercise, and body weight—influence their risk, too. A recent study found that lifestyle interventions reduce the risk of developing diabetes, especially among those at high genetic risk.

    The study involved nearly 1,000 middle-aged men with metabolic syndrome—a constellation of health conditions that increases the for diabetes. About half of the men had a low genetic risk for the disease, while the remainder had a high genetic risk. The men participated in a three-year-long group-based lifestyle intervention program that involved dietary counseling, exercise guidance, and weight management. Researchers monitored the men’s health and diabetes incidence throughout the study period.

    They found that the intervention reduced the risk of developing diabetes by 70% among participants with high genetic risk and 31% among those with low genetic risk. However, the latter reduction wasn’t statistically significant. The intervention promoted weight loss and prevented increased blood glucose levels in both groups.

    These findings suggest that lifestyle interventions can have marked effects on diabetes incidence in people at risk. Exercise, in particular, makes the body’s tissues more sensitive to insulin, helping to maintain healthy blood glucose levels. Learn more about how exercise may prevent diabetes in this episode featuring Dr. Guido Kroemer.

  • The choices people make in their daily lives—such as whether to smoke, what to eat, and how active they are—can have a profound effect on their cancer risk. These behaviors are not just habits; they are powerful determinants of health. A recent study found that nearly half of cancer deaths among adults in the U.S. are linked to modifiable lifestyle factors.

    The researchers used national data to estimate cancer cases and deaths for 30 types of cancer. They examined the effects of modifiable risk factors such as smoking, obesity, alcohol consumption, diet, physical inactivity, and ultraviolet light exposure on cancer risk.

    They found that 40% of cancer cases and 44% of cancer deaths were linked to modifiable risk factors. Smoking was the leading contributor, accounting for nearly 20% of cases and more than 28% of deaths. Other major risk factors included excess body weight and alcohol use, accounting for more than half of the cases and deaths for 19 out of 30 cancer types.

    These findings suggest that people can reduce their risk of developing cancer by making informed lifestyle choices. Exercise is a powerful lifestyle tool in cancer prevention and survival. During exercise, increased blood flow subjects circulating cancer cells to powerful forces, causing them to self-destruct. Learn more in this clip featuring Dr. Rhonda Patrick.

  • Photodynamic therapy is a widely used treatment for actinic keratoses—rough, scaly patches on the skin that may develop into cancer if not treated. Typically, complete skin healing after photodynamic therapy takes between five and ten days, but a recent study found that healing rates differ markedly between vegans and omnivores.

    The study involved 60 patients (30 omnivores and 30 vegans) who were treated with photodynamic therapy for actinic keratosis. Researchers compared side effects using a local skin response score at three intervals: three days, seven days, and 30 days post-treatment. They also noted the time required for complete skin healing in both groups.

    They found that vegans experienced higher total local skin response scores at each interval, indicating they had more severe side effects. On day three, vegans had considerably more swelling and blistering than omnivores. By day seven, they had more redness, peeling, swelling, and blistering. At thirty days, redness and peeling were still more noticeable in vegans. The time required for complete skin healing was notably longer for the vegan group.

    These findings suggest that diet influences healing time following photodynamic therapy, with vegans being more prone to prolonged side effects and slower healing.

    Photodynamic therapy involves the use of a photosensitizing agent (a drug that becomes activated by light) and a specific wavelength of light. When the photosensitizer is exposed to this light, it produces reactive oxygen species that can destroy targeted cells. It differs from photobiomodulation—often called red-light therapy—which uses low-intensity light to stimulate cellular processes and promote healing and pain relief. Learn more about photobiomodulation in our overview article.

  • How often a person has a bowel movement—influenced by what they eat or drink or other lifestyle factors—affects their gut microbiome’s overall makeup, ultimately influencing disease risk. A recent study found that infrequent bowel movements drive the accumulation of toxic metabolites that impair kidney function.

    The study involved more than 1,000 healthy adults. Researchers collected information about the participants' bowel movement frequency and lifestyles. They categorized the participants according to the frequency of their bowel movements: diarrhea, high-normal (one to three daily), low-normal (three to six weekly), or constipation. Then, they analyzed their gut microbial makeup and measured proteins and metabolites in their blood.

    They found that participants with lower bowel movement frequency tended to be female, young, or thin and had gut microbial populations that mirrored those of people with Parkinson’s disease—who often have constipation. They also had high levels of blood metabolites associated with kidney dysfunction, neuroinflammation, cognitive decline, and vascular disease. These participants were more likely to report low fruit and vegetable intake, high snack intake, and anxiety and/or depression.

    Frequent bowel movements may reduce the overall diversity of microbes in the gut, increasing the risk of inflammation and poor health. However, infrequent bowel movements may increase levels of toxic microbial metabolites in the urine, driving chronic kidney disease and neurodegenerative disorders.

    These findings suggest that bowel movement infrequency alters gut microbial populations and increases the production of harmful metabolites. Fruits and vegetables contain bioactive compounds and dietary fiber that benefit gut health and promote regular bowel activity. This smoothie is a tasty way to get more fruits and vegetables into your diet.

  • Carbohydrates are the principal driver of insulin secretion, facilitating the uptake and metabolism of this macronutrient. However, a recent study found that fats and proteins also stimulate insulin secretion, potentially affecting people with type 2 diabetes.

    Researchers collected pancreatic islet cells responsible for insulin secretion from 140 donors after their deaths. About half of the donors had type 2 diabetes. They exposed the cells to carbohydrates, fats, and proteins and assessed insulin secretion.

    They found that most donors' islet cells exhibited a robust insulin response to carbohydrates, a moderate response to protein, and a low response to fat. However, some donors' cells elicited responses to protein (9%) and fat (8%) greater than their response to carbohydrates. Cells from donors with type 2 diabetes exhibited diminished responses to carbohydrates and fats, but their protein response was preserved.

    These findings suggest that insulin responses to macronutrients differ among individuals, with some preferentially responding to proteins and fats over carbohydrates. They also suggest that higher protein diets could benefit people with type 2 diabetes. Some evidence suggests that current guidelines for protein intake are too low, with implications for people more responsive to protein. Learn more about protein requirements in this clip featuring Dr. Stuart Philips.

  • Olive oil is rich in bioactive compounds, including polyphenols, carotenoids, and oleic acid. It’s a fundamental component of the Mediterranean diet and is associated with a wide range of health benefits. A recent study found that high olive oil intake—more than 3 tablespoons daily—reduces the risk of early death from all causes by 20%.

    Researchers analyzed data from nearly 23,000 adults enrolled in a long-term cohort study in Italy. Participants completed questionnaires about their olive oil consumption, defined as high (3 tablespoons or more daily) or low (1.5 tablespoons or less daily). The researchers collected information about the participants' lifestyles, assessed their overall diet quality, and measured their biomarkers associated with chronic disease risk.

    They found that compared to low olive oil intake, high intake lowered the risk of early death from all causes by 20%, cancer by 23%, and cardiovascular disease by 25%. However, They found that the effect of high olive oil intake on reducing the risk of dying from all causes and cancer was slightly lower when considering the participants' biomarkers.

    These findings suggest that olive oil reduces the risk of early death from all causes, including cancer and cardiovascular disease. The polyphenols in olive oil exert potent antioxidant, anti-inflammatory, and anti-cancer effects. Learn more about the health benefits of polyphenols in our overview article.

  • Mild cognitive impairment is often a precursor to Alzheimer’s disease, marking the initial stages of cognitive decline that precede more severe dementia. Evidence suggests lifestyle factors mediate the progression of mild cognitive impairment. A recent study found that intensive lifestyle modification improves cognitive and functional performance and slows disease progression in older adults with mild cognitive impairment.

    Researchers conducted a randomized controlled trial involving 49 participants aged 45-90 with mild cognitive impairment or early dementia due to Alzheimer’s disease. Half of the participants received the usual care, while the other half received a 20-week intensive lifestyle intervention. The researchers assessed the participants' cognitive and functional performance and measured plasma biomarkers associated with Alzheimer’s before and after the intervention.

    They found that participants in the intervention group showed considerable improvements in cognition and function compared to the control group. In addition, Aβ42/40 ratios increased in the intervention group but decreased in the control group.

    The Aβ42/40 ratio is a measure of the relative levels of two forms of amyloid-beta protein (Aβ42 and Aβ40) in the blood or cerebrospinal fluid. It is a biomarker used to assess the presence and progression of Alzheimer’s disease. Lower ratios typically indicate higher levels of brain amyloid-beta plaques, a hallmark of the disease. An increase in the Aβ42/40 ratio, as observed in the intervention group, suggests a potential reversal or slowing of amyloid-beta plaque accumulation, indicating an improvement in disease pathology.

    These findings suggest that intensive lifestyle modification has profound effects on Alzheimer’s disease progression in older adults with mild cognitive impairment. FoundMyFitness has a wealth of information about the various components used in this intensive protocol, which included:

  • Mitochondrial function declines with aging, driving many age-related conditions, including Alzheimer’s disease. A recent study in mice found that urolithin A, a compound derived from pomegranates and walnuts, promotes mitophagy – the targeted destruction of damaged mitochondria – in the brain.

    Researchers fed older mice urolithin A (200 milligrams per kilogram of body weight) daily for five months. They subjected the animals to various learning and memory tests, assessed their sense of smell, and examined their brains.

    They found that urolithin A markedly improved the animals' learning, memory, and sense of smell, enhanced memory-related brain functions, and reduced the accumulation of amyloid-beta and tau protein (hallmarks of Alzheimer’s disease). Urolithin A also improved the function of lysosomes, cellular structures that play a crucial role in mitophagy, by breaking down and recycling damaged mitochondria.

    These findings suggest that urolithin A boosts mitophagy in mice, improving brain health and cognitive function. Urolithin A is a byproduct of gut microbial metabolism of ellagic acid, a bioactive compound found in pomegranates and walnuts. The capacity to form urolithin A from ellagic acid varies considerably from person to person (depending on gut microbial composition) and decreases with age.

    Due to the low quantities of ellagic acid in foods and the poor conversion rate, achieving a human dose comparable to that used in this study likely would require supplemental intake. Nevertheless, the findings align with other evidence suggesting that long-term dietary intake of foods containing ellagic acid benefits cognitive health.

  • While brain aging is an inevitable part of growing older, lifestyle factors, particularly diet, can influence the rate at which this aging occurs. A recent study found that older adults with diets rich in omega-3 fatty acids, antioxidants, and vitamins demonstrate slower brain aging and better performance on cognitive tests.

    Researchers administered cognitive tests and brain imaging scans to 100 healthy older adults. They also measured 13 nutrition-related biomarkers in the participants' blood.

    They identified two brain aging patterns among the participants, with one group exhibiting accelerated aging and the other slower aging. Further analysis revealed that distinct dietary patterns distinguished the two groups. In particular, the intake of specific nutrients positively influenced brain health and cognitive function, including: - Alpha-linolenic acid (an omega-3 fatty acid found in nuts and seeds, such as walnuts and chia) - Eicosapentaenoic acid (an omega-3 fatty acid found in fatty fish, such as salmon) - Lutein (a polyphenol found in green leafy vegetables, such as kale) - Zeaxanthin (a polyphenol found in brightly colored vegetables, such as orange bell peppers and butternut squash) - Vitamin E (found in seeds and nuts, such as sunflower seeds and hazelnuts) - Choline (found in a variety of foods, including eggs and soybeans) These patterns were consistent even when considering the participants' demographics, fitness levels, and body measurements.

    These findings suggest that nutrient-rich diets are critical for maintaining cognitive health and decelerating the brain’s aging process. They also highlight the importance of dietary choices as potential tools to manage and mitigate age-related cognitive decline. Learn about other lifestyle choices that slow cognitive and physical aging in this episode featuring Dr. Rhonda Patrick.

  • Aggressive behaviors, such as hitting, yelling, or threatening, can cause physical or emotional harm to others. Research indicates that poor nutrition may contribute to these behaviors, suggesting that dietary interventions could be helpful strategies for reducing them. A recent review and meta-analysis found that omega-3s can reduce aggressive behaviors by as much as 28 percent in children and adults.

    Researchers analyzed the findings of 29 randomized controlled trials investigating the effects of omega-3s on behavior. The trials included more than 3,900 participants and involved children and adults of varying ages.

    Their analysis revealed that omega-3s exerted a short-term effect on behavior, with reductions ranging from 16 to 28 percent, regardless of age, gender, baseline diagnosis, treatment duration, or dose. Interestingly, omega-3s reduced reactive aggression (impulsive behavior in response to a perceived threat) and proactive aggression (premeditated to achieve a specific goal).

    These findings suggest that omega-3s positively influence behavior in children and adults and offer a potential strategy for moderating behavior problems in multiple settings, including the community, prisons, and clinics.

    Omega-3 fatty acids are essential for normal brain function, contributing to cell membrane structure, nerve growth, neurotransmitter regulation, and reducing inflammation. Learn more about omega-3s in our comprehensive overview article.

  • The body’s circadian rhythms – its 24-hour biological, hormonal, and behavioral cycles – are optimized for daytime eating. Consequently, eating in the late evening or nighttime hours may increase a person’s risk of developing chronic diseases, such as type 2 diabetes. A recent study found that nighttime eating increased the risk of premature death from diabetes by as much as 131 percent.

    The investigation included more than 41,000 adults enrolled in NHANES, an ongoing study that assesses the health and nutritional status of people in the U.S. Researchers gathered information about the participants' eating habits (including timing and food quality) and tracked their health and death rates for about nine years.

    They found that compared to eating before 10 p.m., - Eating between 11 p.m. and midnight increased the risk of premature death from diabetes by 131 percent. - Eating between midnight and 1 a.m. increased the risk of premature death from any cause by 38 percent. - Eating between 1 a.m. and 2 a.m. increased the risk of premature death from cancer by 109 percent.

    When they considered the frequency of eating late, they found that eating at night at least once increased the risk of premature death from all causes, including diabetes. Food quality influenced death risk, too, with high-calorie foods increasing the risk of premature death from all causes by 21 percent and from diabetes by 97 percent. Participants who ate late tended to have higher HbA1c, fasting glucose, and oral glucose tolerance test results, indicative of poor glucose metabolism.

    These findings suggest that late-night eating, particularly high-calorie foods, increases the risk of early death from all causes, especially diabetes. Shift work, jet lag, parenting, and modern lifestyles contribute to late-night eating, increasing disease and early death risk. Learn more in this clip featuring Dr. Satchin Panda.

  • The body’s appetite feedback circuit is a sophisticated system that regulates hunger and satiety to maintain energy balance. Suppressing this circuit is essential to successful weight loss before reaching a plateau. A recent study found that weight-loss interventions vary in their capacity to overcome the body’s appetite feedback circuits by as much as threefold.

    A researcher used a validated mathematical model to simulate the body’s weight-loss response to calorie restriction, glucagon-like peptide receptor agonists (GLP-1 RAs, a class of drugs primarily used to treat type 2 diabetes and obesity), and bariatric (gastric bypass) surgery. The model predicted how these interventions influenced body weight by simulating changes in caloric intake, energy use, and appetite over time.

    He found that weight loss plateaued at around 12 months with calorie restriction and at around 24 months with GLP-1 RAs or gastric bypass surgery. The drugs and surgery were between 40 and 70 percent more effective at suppressing appetite than calorie restriction, aligning with data indicating that most people find calorie restriction challenging to adhere to, especially for an extended period.

    These findings suggest that weight-loss interventions vary in their capacity to overcome the body’s appetite feedback circuits, influencing their effectiveness. Unfortunately, many people regain weight after successful weight loss, possibly due to changes in their gut microbiome. Learn more in this episode featuring Dr. Eran Elinav.

  • Maintaining muscle mass as we age requires a comprehensive approach encompassing nutrition and regular physical activity. However, many older adults don’t consume adequate dietary protein and may lead sedentary lives, due to injuries, chronic illnesses, or joint problems. A recent study found that older adults who increased their dietary protein intake and engaged in regular exercise showed marked improvements in multiple health and fitness parameters.

    The study involved 97 older adults (average age, 64) with low dietary protein intake (less than 1 gram per kilogram of body weight daily) who had experienced at least one fall in the past year. Half of the participants received a daily serving of a protein-enriched soup (providing 24 to 30 grams of protein) and engaged in one hour of group exercise (aerobic and resistance) each week for 12 weeks. The other half received nutrition education training at the beginning of the study and maintained their normal activity levels.

    At the end of the study, sedentary participants showed improvements in handgrip strength only. However, the participants who consumed the protein-rich soup and exercised regularly showed improvements in waist circumference, walking distance, lower body strength, functional mobility, handgrip strength, nutritional status, serum triglycerides, HDL cholesterol, and DHEA-S.

    DHEA-S (dehydroepiandrosterone sulfate) is a naturally occurring precursor to estrogen and testosterone. These steroid hormones exert anabolic effects by enhancing the bioavailability of insulin-like growth factor-1 in muscles, facilitating muscle growth and repair.

    These findings suggest that increasing dietary protein and activity levels in older adults improves multiple health and fitness parameters. Interestingly, most of the participants in this study were female. Evidence suggests women typically consume less protein than men. In this clip, Dr. Stuart Phillips provides some insights to help older women get sufficient protein to support muscle health.

  • Although exercise is the primary stimulus for maintaining muscle mass and strength, nutritional support is essential, too, especially in the form of dietary protein. However, most people’s protein intake is skewed toward later in the day, with little to no protein at breakfast. A recent review found that older adults with higher protein intake at breakfast had greater muscle mass.

    Researchers reviewed the findings of 15 studies examining associations between protein intake and muscle mass. The various studies included cross-sectional, case-control, cohort, and randomized controlled trials involving primarily older males and females. However, one study included middle-aged females, and one included young males.

    The researchers found that consuming a high-protein breakfast (ranging between 0.27 and 0.53 grams per kilogram bodyweight) increased muscle mass, particularly in older adults. While some of the studies' findings suggested that a high-protein breakfast enhanced muscle strength, the evidence was inconsistent across all studies.

    These findings suggest that increasing protein intake at breakfast supports muscle mass maintenance. The investigators posited that increasing protein intake during breakfast could be a beneficial strategy for supporting muscle health for active adults or those in resistance training. However, individual results may vary, indicating the need for more personalized dietary recommendations. Learn more about the role of dietary protein in building and maintaining muscle in this episode featuring Dr. Stuart Phillips.

  • Plant-based meat substitutes are made from non-meat sources, such as legumes or wheat gluten. They typically mimic the sensory profile of meat products and are popular among those wishing to reduce their animal protein intake for ethical or health reasons. A recent study found that plant-based meat substitutes did not benefit cardiometabolic health in people at risk for type 2 diabetes.

    The study involved 82 adults at risk for type 2 diabetes. Half of the participants ate an animal-based diet, while the others swapped out their usual animal-based foods for plant-based meat substitutes. Researchers assessed their blood lipids (triglycerides, LDL, HDL, and total cholesterol), glycemic control, insulin sensitivity, and blood pressure before and after the eight-week intervention.

    They found that participants who ate the plant-based meat substitutes had higher fiber, sodium, and potassium intake than those who ate animal meat. Their blood lipids showed little improvement, but their diastolic blood pressure decreased, and their insulin sensitivity increased. However, those who ate the animal meat diet had better glycemic control than those on the plant-based diet.

    These findings suggest that plant-based meat substitutes don’t improve cardiometabolic health in people at risk for type 2 diabetes. However, robust evidence demonstrates that high-intensity interval training (HIIT) profoundly affects cardiometabolic health. Learn more in this episode featuring Dr. Martin Gibala.

  • Age-related macular degeneration is the leading cause of vision loss in older adults. However, evidence suggests that some dietary components reduce the risk of the disease. A recent study found that eating blueberries cuts the risk of age-related macular degeneration by 64 percent.

    The study involved roughly 35,000 middle-aged and older women enrolled in the Women’s Health Study. Researchers used questionnaires to collect information about the women’s blueberry intake and eye health for about 11 years.

    They found that eating blueberries one to three times a month reduced the risk of age-related macular degeneration by 10 percent, eating them once a week by 29 percent, more than once a week by 32 percent, and two or more times a week by 64 percent. Eating more blueberries didn’t show a protective effect against developing cataracts; however, higher anthocyanin intake did confer a 10 percent reduction in risk.

    Blueberries are rich in anthocyanins – a class of flavonoid compounds that exert robust antioxidant and anti-inflammatory properties via hormetic effects. Learn about the hormetic effects of anthocyanin-rich blueberries as well as other hormetic compounds in this smoothie recipe video.

  • Obesity and overweight are growing global public health concerns, especially among young people. Evidence suggests that apple cider vinegar supports weight loss and improves metabolic health. A recent study found that young people who took apple cider vinegar for 12 weeks lost more weight and exhibited better metabolic parameters than those who took a placebo.

    The study involved 120 teens and young adults with overweight or obesity. Participants received 5, 10, or 15 milliliters (5 milliliters = 1 teaspoon) of apple cider vinegar or a placebo diluted in water daily for 12 weeks. They didn’t make any changes to their diets or activity levels. Researchers measured the participants' anthropometrics (weight, body mass index, waist/hip circumferences, and body fat ratio) and blood glucose, triglyceride, and cholesterol levels at the beginning of the study and again at four-week intervals.

    They found that participants who took apple cider vinegar lost weight in a dose- and time-dependent manner, with those taking higher doses manifesting the greatest weight loss, which increased as the study progressed. All anthropometric measures improved, too, as did blood glucose, triglyceride, and cholesterol levels. None of the participants taking the vinegar experienced any adverse or ill effects.

    These findings suggest that apple cider vinegar promotes weight loss and improves metabolic parameters in young people with overweight or obesity. The investigators noted that these effects occurred without changes to the participants' diets or activity levels, suggesting the effects arose from the vinegar itself. Apple cider vinegar is made by fermenting apple juice. It is rich in vitamins, minerals, amino acids, and polyphenols such as flavonoids, which may confer some of apple cider vinegar’s benefits. Learn about the health benefits of other polyphenols in our overview article.

  • Cinnamon is one of the most consumed spices in the world, popular in both sweet and savory dishes in many cuisines. Evidence suggests cinnamon improves lipid profiles and protects against damage induced by oxidative stress, improving metabolic profiles in people with type 2 diabetes. New research now shows that a component of cinnamon may promote hair growth.

    Researchers studied the effects of cinnamic acid, a component of cinnamon, on hair growth. First, they treated dermal papilla cells (cells involved in hair formation and development) with varying concentrations (0 to 2,000 micrograms per milliliter, µg/mL) of cinnamic acid. They found that low to moderate concentrations of the compound (less than 500 µg/mL) increased the production of genes involved in hair growth and enhanced the activity of receptors for oxytocin, a hormone, in the cells.

    Next, they studied the effects of cinnamic acid on hair follicle organoids called follicloids. Organoids are three-dimensional tissue cultures produced from stem cells that mimic the structure and activity of the organ from which they are derived. They applied varying concentrations (0, 50, 100, and 500 µg/mL) of cinnamic acid to the follicloids and measured hair growth for 10 days. They found that concentrations of 100 to 500 µg/mL of cinnamic acid promoted hair growth in the follicloids by the eighth day.

    These findings suggest that cinnamic acid is a viable option for promoting hair growth by targeting the oxytocin receptor. Recent research found that oxytocin promotes hair growth, but because oxytocin breaks down rapidly and is a relatively large molecule, it isn’t a good candidate for use in pharmaceutical or cosmetic treatments to grow hair. However, cinnamic acid is a naturally occurring polyphenol with potent antioxidant, anti-inflammatory, and anti-cancer properties. Learn more about polyphenols in our overview article.

  • A ketogenic diet – a high-fat, low-carbohydrate dietary pattern – offers potential benefits in various health contexts, including weight management and seizure control. Some evidence suggests that the ketogenic diet is beneficial in preventing or treating neurodegenerative diseases, such as Alzheimer’s and dementia. A recent study in older mice found that a ketogenic diet improves memory functions and increases lifespan.

    Researchers compared the effects of a seven-month ketogenic diet to a standard diet in mice prone to developing Alzheimer’s-like symptoms. They examined the hippocampal region of the animals' brains, a crucial area for memory and learning, to gauge the diet’s effects on synaptic plasticity – the brain’s ability to form and reorganize synaptic connections, especially in response to learning or new experiences.

    They found that mice on the ketogenic diet experienced restoration of their long-term potentiation – a measure of synaptic strength and a fundamental mechanism for learning and memory – to levels comparable to healthy mice. They attributed this restoration to the marked elevation of beta-hydroxybutyrate (BHB), a ketone body produced during the ketogenic diet. They also found that the diet triggered enhancements in several key pathways and molecules associated with synaptic plasticity, including notable increases in specific enzymes and brain-derived neurotrophic factor (BDNF), particularly in female mice.

    BDNF is crucial for cognitive functions, providing support for neuronal survival, growth, and differentiation and enhancing learning and memory by strengthening and creating synaptic pathways. Elevated BDNF levels correlate with better cognitive performance, whereas its deficiency is linked to various mental and neurodegenerative disorders, highlighting its significance in brain health. Learn more about BDNF in our overview article.

    These findings suggest that a ketogenic diet ameliorates memory impairments and bolsters neuronal health in an Alzheimer’s mouse model, primarily through the action of BHB and its enhancement of synaptic plasticity. Learn more about beta-hydroxybutyrate in our overview article.

  • The gut-brain axis, a bidirectional signaling pathway between the gastrointestinal tract and the nervous system, plays a critical role in human health, including aspects of cognition. Key elements of this pathway are the tens of trillions of microbes that comprise the intestinal microbiota. A recent study found that taking a prebiotic supplement altered the gut microbiota, improving cognitive performance in older adults.

    The randomized controlled study involved 36 older adult twin pairs. One twin within each pair consumed a prebiotic supplement containing inulin and fructo-oligosaccharides for 12 weeks, while the other twin took a placebo. Participants provided information about their daily dietary intake and underwent cognitive tests before and after the supplement intervention. Researchers analyzed the participants' gut microbial populations.

    They found that the prebiotic supplement increased the number of Bifidobacterium – a type of bacteria commonly associated with gut health – in the participants' guts. Those who took the prebiotic performed better on cognitive tests than those who took the placebo. In particular, they performed better on a paired associate learning test, a memory assessment commonly used for the early detection of Alzheimer’s disease.

    These findings suggest that prebiotics influence cognitive health via gut-brain axis interactions. Prebiotics are food components that support the maintenance of a healthy microbiota and create an environment conducive to its survival. Inulin and fructo-oligosaccharides are among the most abundant prebiotics in the human diet, present in apples, bananas, legumes, and dietary supplement forms. Their fermentation by gut microbiota produces short-chain fatty acids, including acetate, propionate, and butyrate.

  • Sarcopenia is an age-related condition involving the gradual loss of muscle mass and strength. Older adults with sarcopenia are at greater risk for frailty, falls, loss of independence, and early death. A 2022 study found that higher dietary fiber intake maintains muscle mass in older adults.

    Researchers assessed the physical capabilities (including balance, walking speed, and grip strength) of 981 older adults. They also measured their muscle mass using DEXA. Participants reported their dietary fiber intake and wore accelerometers to track their physical activity.

    The DEXA scans revealed that women who consumed more fiber had considerably greater muscle mass than those who ate less. Men who consumed more fiber also had greater muscle mass, but only in those without metabolic syndrome. The associations were consistent even when considering physical activity and protein consumption.

    These findings suggest that dietary fiber protects against muscle loss in older adults. Sources of dietary fiber include fruits, vegetables, whole grains, and legumes. People who follow a lower carbohydrate diet might find getting enough fiber challenging. Dr. Dominic D'Agostino provides some tips on how to get plenty of fiber even when following a ketogenic diet.

  • Sleep deprivation profoundly affects the human body, negatively influencing cognitive performance, cardiovascular health, and metabolism. Evidence suggests creatine counters some of the harmful effects of sleep deprivation. A recent study found that a single dose of creatine monohydrate improved cognitive performance and prevented harmful metabolic effects in sleep-deprived people.

    The study involved 15 healthy participants who received a single large dose of creatine monohydrate (0.35 grams per kilogram of body weight) or a placebo to assess creatine’s effects on cognitive function during prolonged wakefulness. Participants underwent evaluations before and several hours after taking their respective treatments in the context of 21 hours of sleep deprivation. They underwent brain imaging scans and cognitive tests to measure the effects of creatine on brain chemistry and cognitive performance.

    The scans and tests revealed that creatine induced several critical changes in the brain, including:

    Increasing the ratio of phosphocreatine to inorganic phosphate, providing more energy for brain cells.

    Boosting the levels of ATP, supporting better brain activity and energy management.

    Altering the ratio of creatine to N-acetylaspartate, enhancing brain cell health and boosting energy reserves.

    Maintaining optimal brain pH levels, supporting brain function and neurotransmitter signaling.

    Enhancing cognitive performance and processing speed, making thinking and processing information faster and more efficient.

    These findings suggest that a large dose of creatine could mitigate some of the harmful effects of sleep deprivation on the brain and cognitive function. Creatine is a nitrogen-containing compound produced in the liver and kidneys and stored in the brain and muscles. It plays an essential role in the recycling of ATP and is widely used as a dietary supplement to build and maintain muscle mass. Although creatine is available in many forms, the bulk of the research on the compound has centered on creatine monohydrate. Learn more about creatine in this clip featuring Dr. Stuart Phillips.

  • Irritable bowel syndrome (IBS) is a digestive disorder characterized by abdominal cramping, gas, diarrhea, and constipation. The condition affects as many as 10 percent of people worldwide and has no cure. A recent study shows that adopting three or more healthy lifestyle behaviors may reduce the risk of IBS by as much as 42 percent.

    The study involved more than 64,000 people enrolled in the UK Biobank database. Researchers collected information about the participants' dietary intake and whether they engaged in any of five healthy lifestyle behaviors: never smoking, getting optimal sleep, engaging in vigorous physical activity, eating a quality diet, and moderating their alcohol intake.

    They found that 11.8 percent of the participants did not practice any of the five critical healthy behaviors; 32.1 percent practiced one, 34.1 percent practiced two, and 21.9 percent practiced three to five healthy behaviors. As participants engaged in more healthy behaviors, their likelihood of developing IBS decreased, with those practicing one healthy behavior having a 21 percent lower risk, those with two healthy behaviors having a 36 percent lower risk, and those engaging in three to five healthy behaviors having a 42 percent lower risk. These findings were consistent across various groups, regardless of age, sex, job status, where they lived, history of gastrointestinal infection, endometriosis, family history of IBS, or other lifestyle habits.

    These findings suggest that adopting multiple healthy lifestyle behaviors, such as not smoking, staying physically active, and getting good sleep, can significantly reduce the risk of developing IBS. Learn more about factors that influence gut health in this episode featuring Dr. Eran Elinav.

  • Time-restricted eating is a dietary pattern that restricts the time during which a person eats to a specific window, such as a “16:8" pattern, where they fast for 16 hours a day and consume food only during the remaining eight hours. Evidence suggests that time-restricted eating improves cognitive function, supports weight loss, and reduces systemic inflammation. Findings from a recent review and meta-analysis suggest that time-restricted eating also reduces the risk of cardiovascular disease.

    Researchers analyzed the findings of 33 studies involving 1,725 participants investigating the effects of time-restricted eating on markers of cardiovascular health. They conducted a sub-group analysis to determine how age, health characteristics, and eating patterns influenced the effects of time-restricted eating.

    They found that the effects of time-restricted eating on cardiovascular disease varied according to a person’s risk factors, age, and when they ate. The table below presents their findings for the optimal time-restricted eating for different groups.

    This meta-analysis and review identifies the optimal time-restricted eating interventions for blood pressure, obesity, lipids, and glucose. It effectively provides a best-practices guide for people interested in implementing time-restricted eating as a lifestyle modification to improve cardiovascular health. Learn more about time-restricted eating in this episode featuring Dr. Satchin Panda.

  • Cinnamon is one of the most consumed spices in the world, popular in both sweet and savory dishes in many cuisines. Evidence suggests cinnamon improves lipid profiles and protects against damage induced by oxidative stress. A recent systematic review and meta-analysis found that cinnamon helps maintain healthy blood glucose levels and reduces insulin resistance in people with type 2 diabetes.

    Researchers analyzed the findings of 24 clinical trials investigating the effects of cinnamon supplementation on blood glucose levels. The various trials included more than 1,800 participants from 11 nations.

    The analysis revealed that cinnamon supplementation reduced fasting blood glucose levels, hemoglobin A1c concentrations, and insulin resistance (without lowering insulin) in people with type 2 diabetes. The trials varied in duration from six to 16 weeks, and daily cinnamon doses ranged from 120 to 6,000 milligrams, averaging 2,100 milligrams – roughly a teaspoon.

    These findings suggest that cinnamon improves symptoms of type 2 diabetes and may be a valuable adjunct to traditional therapies. Cinnamon is rich in polyphenols, a broad class of plant bioactive compounds. Learn more about polyphenols in our overview article.

  • Obesity, which affects more than 40 percent of U.S. adults, arises when the body stores excess fat, primarily in adipose tissue. While adipose tissue is an important source of energy, its capacity to produce energy in the setting of obesity diminishes, complicating weight loss efforts. A recent study demonstrates that obesity promotes fragmentation of the mitochondria in adipose cells, resulting in smaller and less effective mitochondria with reduced fat-burning capacity.

    Researchers fed mice an obesogenic diet and assessed its effects on their fat cells' mitochondrial function. Then, they analyzed gene activity in fat samples collected from people with obesity.

    They found that after eating a high-fat diet, mitochondria in the animals' adipose cells underwent fragmentation, forming smaller, less efficient mitochondria with diminished fat-burning capabilities. This metabolic alteration was orchestrated by the activity of RaIA, a molecule that serves various roles, one of which involves assisting in the breakdown of dysfunctional mitochondria. Deleting this gene in the mice prevented excessive weight gain despite consuming an obesogenic diet, highlighting RaIA’s crucial role in transitioning from a healthy weight to obesity. They also found evidence of increased gene activity in people with obesity that corresponded with persistent elevation in RalA.

    These findings suggest that obesity induces fragmentation of mitochondria, compromising their function and driving a vicious cycle of diminished fat-burning capability and increased body fat gain. Evidence suggests cold exposure and fasting promote weight loss. Learn more in this episode featuring Dr. Ray Cronise.

  • Whole fruits are rich in vitamins, minerals, and bioactive compounds that promote health. They also contain essential fiber, which supports digestion and regulates blood sugar levels. Fruit juices, on the other hand, contain little fiber, are high in natural sugars, and can cause rapid blood sugar spikes, impairing metabolism. A recent systematic review and meta-analysis found that consuming 100 percent fruit juice promotes weight gain in children.

    Researchers analyzed the findings of 42 randomized clinical trials investigating the effects of consuming 100 percent fruit juice on body weight. The various trials included more than 45,000 children and 268,000 adults.

    They found that for every additional serving of juice (defined as 8 ounces) per day, the children showed a modest increase in body mass index, a proxy for body fatness. However, the findings in adults were mixed, with studies that didn’t adjust for caloric intake observing greater body weight gain than those that didn’t.

    These findings suggest that a single serving of 100 percent fruit juice daily promotes weight gain in children – a noteworthy finding considering that roughly half of children and teens in the U.S. consume at least one serving of fruit juice a day. An 8-ounce serving of 100 percent orange juice contains about 110 calories and 20 grams of sugar, while a medium-sized whole orange contains approximately 62 calories and 12 grams of sugar. Encouraging the consumption of whole fruits versus fruit juices may influence body weight in children.

  • In the setting of obesity, adipocytes (fat cells) enlarge to accommodate immense quantities of fat. These specialized cells eventually become dysfunctional, releasing inflammatory proteins and activating immune cells called macrophages. In turn, macrophage activation promotes a vicious cycle of inflammation and further dysfunction, increasing the risk of many chronic diseases, including cardiovascular disease and cancer. A recent review and meta-analysis found that time-restricted eating reduces inflammatory markers and leptin.

    Researchers reviewed the findings of randomized-controlled trials investigating the effects of time-restricted eating on inflammation. Their analysis included 25 trials involving 936 participants.

    They found that time-restricted eating reduced participants' pro-inflammatory markers (C-reactive protein, TNF-alpha, and interleukin-6) and increased levels of adiponectin, a protein produced by adipose tissue that regulates glucose levels and fatty acid breakdown in the body. Time-restricted eating also reduced the participants' leptin, a hormone that drives food intake.

    These findings suggest that time-restricted eating is a viable strategy for reducing inflammation. Previous research has shown that time-restricted eating promotes weight loss in people with obesity.

    Time-restricted eating is a dietary pattern that limits food intake to certain hours of the day without overtly reducing caloric intake. It exploits the body’s innate 24-hour patterns and provides the body an essential downtime where it can focus on DNA and cellular repair and restoration rather than digestion. The most common version of time-restricted eating is a “16:8” pattern, where all the day’s calories are consumed within an eight-hour window, leaving 16 hours for fasting, including the hours during which a person is asleep. Learn about the many health benefits associated with time-restricted eating in this clip featuring Dr. Satchin Panda.

  • With age, cognitive and metabolic dysfunction increases, often coinciding. However, evidence suggests that consuming berries improves cognitive and metabolic health. A recent study found that strawberry consumption improved memory and mood in overweight people with mild cognitive decline.

    Researchers recruited 34 overweight middle-aged adults with insulin resistance who reported mild cognitive decline. Half of the participants consumed a strawberry powder supplement daily for 12 weeks, while the other half consumed a placebo. Both groups abstained from all berry consumption throughout the study. The researchers assessed the participants' cognitive and metabolic functions and moods before and after the intervention.

    They found that those who consumed the strawberry powder exhibited better memory function and fewer symptoms of depression than those who consumed the placebo. However, they did not show any improvements in metabolic function.

    These findings suggest that strawberry supplementation improves cognitive function in middle-aged adults, potentially reducing the risk of dementia, but has little effect on metabolic function. The study’s authors attributed the lack of metabolic response to the relatively low dose and the study’s short duration.

    Strawberries are rich in anthocyanins, a class of polyphenolic compounds that exert potent antidiabetic, anticancer, anti-inflammatory, and anti-obesity effects in humans. Anthocyanins lend their characteristic blue, red, or purple hues to strawberries, blueberries, and other fruits and vegetables. Learn about other polyphenols in our overview article.

  • Coronary artery disease is a cardiovascular condition characterized by the gradual buildup of plaque within the coronary arteries, reducing blood flow to the heart muscle. This narrowing of the arteries can result in chest pain (angina), heart attacks, and impaired heart function, posing a considerable risk to cardiovascular health. A recent study found that omega-3 fatty acids reduce plaque burden in patients with low-to-moderate coronary artery disease risk.

    Researchers recruited 106 patients with low-to-moderate coronary artery disease risk who underwent computed tomography angiography (CTA) – an imaging test that visualizes the coronary arteries. Half of the patients were taking omega-3 fatty acids, and the other half were not. The researchers ranked the patients based on the extent of their coronary artery plaque accumulation and other aspects of arterial disease.

    They found that those who took omega-3s had less total and non-calcified plaque burden than those who didn’t. The risk of having high-risk (lipid-rich) plaque was lower among those who took omega-3s (3.8 percent versus 32 percent). On average, those who took omega-3s had been doing so for about three years.

    These findings demonstrate an association between omega-3s and lower coronary high-risk plaque and total non-calcified plaque burden, suggesting that omega-3s exert direct anti-atherogenic effects.

    Omega-3 fatty acids (DHA and EPA) likely provide vascular protection through various mechanisms involving lipid metabolism and anti-inflammatory and anti-clotting pathways. In addition, evidence suggests that DHA and EPA are directly incorporated into vessel walls, lowering triglycerides. Byproducts of omega-3 metabolism called specialized pro-resolving mediators (SPMs) may play roles, too. Learn more about omega-3s heart-healthy effects in this short video featuring Dr. Rhonda Patrick.

  • Plant-based dietary patterns are typically higher in fiber, vitamins, minerals, and phytonutrients than other dietary patterns. Consequently, they may confer health benefits that reduce the risk of cardiovascular and metabolic disorders. A recent study found that a vegan diet reduced body weight, LDL (“bad”) cholesterol, and fasting insulin in healthy adults.

    To negate any genetic influences that diet might have on cardiometabolic fitness, researchers recruited 22 pairs of female twins to participate in the study. Within each twin pair, one twin followed a healthy vegan diet for eight weeks, and the other followed a healthy omnivorous diet. The researchers measured the twins' cardiometabolic markers before and after the intervention.

    They found that compared to twins who ate an omnivorous diet, twins who followed a vegan diet experienced reduced body weight, LDL cholesterol, and fasting insulin. Participants following a vegan diet had a lower protein, dietary cholesterol, and vitamin B12 intake and a higher vegetable and dietary iron intake than those on the omnivorous diet. They also reported lower satisfaction with their dietary options.

    The findings from this small study suggest that following a vegan diet confers cardiometabolic benefits in healthy young women, aligning with previous research demonstrating that vegan diets reduce the risk of cardiometabolic disease. They also underscore the considerable influence that diet has on cardiometabolic health. Learn how to avoid dietary deficiencies when following a vegan diet in this clip featuring Rich Roll.

  • Robust evidence supports dietary protein intake to support muscle protein synthesis after resistance training. However, most studies investigating the effects of dietary protein have been conducted in men. A recent study found that a daily protein intake greater than 1.8 grams per kilogram of body weight optimized muscle protein synthesis in trained women.

    Researchers asked 24 young women who regularly engaged in resistance training to engage in two resistance training sessions separated by a four-hour break. After each session, the women consumed 15, 30, or 60 grams of whey protein. These amounts provided the women 1.8, 2.3, and 3.2 grams of protein per kilogram of body weight, respectively. Over 24 hours post-workout, the researchers measured the women’s muscle protein synthesis and blood amino acid levels.

    They found that 15 grams of whey protein had little effect on muscle protein synthesis. However, after consuming 30 or 60 grams of whey protein, the women’s muscle protein synthesis increased, especially in the first eight hours post-workout. Interestingly, there was little difference in muscle protein synthesis between the 30- and 60-gram doses.

    Current dietary guidelines recommend that healthy adults consume 0.8 grams of protein per kilogram of body weight per day. However, this intake level is likely too low for building and maintaining muscle mass. The findings from this study suggest that increasing the recommended amount, ensuring a daily intake of greater than 1.8 grams per kilogram of body weight, will pay the greatest dividends for promoting muscle protein synthesis in trained women. Learn more about the importance of dietary protein in this episode featuring Dr. Stuart Philips.

  • Nutritional ketosis is a powerful tool for managing weight and moderating inflammation. However, most studies on ketosis have been conducted in men and have only assessed short-term effects. A recent study found that nutritional ketosis reduces blood glucose, insulin, and inflammatory markers in healthy women practicing long-term ketosis.

    Researchers asked ten healthy young women who had been maintaining nutritional ketosis for more than a year to alter their dietary habits to suppress ketosis. The study involved three one-week phases: nutritional ketosis, suppressed ketosis, and return to nutritional ketosis. The researchers measured the women’s ketone levels daily; at the end of each phase, they took their women’s body measurements and assessed their metabolic and inflammatory biomarkers.

    They found that when the women suppressed ketosis, their insulin, IGF-1, glucose, and pro-inflammatory markers increased. However, when they returned to ketosis, those markers returned to baseline levels.

    These findings suggest that nutritional ketosis maintains healthy metabolism and suppresses inflammation without altering metabolic flexibility. Other evidence demonstrates that a ketogenic diet promotes weight loss and reduces cancer risk. Learn how to design the optimal ketogenic diet in this episode featuring Dr. Dominic D'Agostino

  • Choline, an essential nutrient found in eggs, meat, fish, beans, and nuts, supports the production of acetylcholine, a neurotransmitter involved in neurogenesis, synapse formation, learning, and memory. Most people living in the US don’t consume enough choline – 550 milligrams per day for men and 425 milligrams per day for women – potentially increasing their risk for various diseases. A 2019 study in mice found that lifelong choline supplementation prevented Alzheimer’s disease and preserved cognitive function.

    Researchers fed mice susceptible to developing Alzheimer’s disease a regular diet or a diet supplemented with choline from early life to old age. When the mice reached the age of 10 months, the researchers assessed the animals' memory function and examined their brain tissue.

    They found that mice that received lifelong choline supplementation had better spatial memory and fewer amyloid-beta plaques in their brains than those on a regular diet. They also found that the mechanisms driving these effects were related to reduced amyloid-beta peptide synthesis, a dampened microglia inflammatory response, and downregulation of the alpha-7 nicotinic acetylcholine and sigma-1 receptors, both of which are critical for various neurological processes.

    These findings suggest that lifelong choline supplementation mitigates Alzheimer’s disease pathology and maintains cognitive function in mice susceptible to the disease. Other research showed that mice that ate a choline-poor diet had higher brain levels of amyloid-beta and tau – two proteins implicated in the pathogenesis of Alzheimer’s disease – than those that ate a choline-rich diet. The mice that ate a choline-poor diet also gained weight, showed signs of altered metabolism, liver damage, and enlarged hearts, and performed poorly on motor skills tests.

    More than 55 million people worldwide live with Alzheimer’s disease. Learn more about the disease and how to prevent it in this episode featuring Dr. Dale Bredesen.

  • A high-protein diet may increase the risk of heart disease, diabetes, and increased body fat, especially in sedentary people. However, a new study in mice demonstrates that resistance training may counter these effects. Mice that ate a high-protein diet and performed resistance exercises gained muscle – not fat – and were more metabolically healthy than sedentary mice on the same diet.

    Researchers fed one group of mice a low-protein diet (7 percent of total calories) and another a high-protein diet (36 percent of total calories). Half of each group performed resistance exercises three times weekly for three months, while the other half remained sedentary. The researchers then compared various parameters, such as body composition, weight, and metabolic indicators, across the different groups.

    They found that the sedentary mice that ate a high-protein diet gained more fat than those on a low-protein diet. However, mice that ate a high-protein diet but engaged in resistance-based training gained muscle mass but not excess body fat. Interestingly, the high-protein-fed mice gained strength faster but, by the study’s end, did not outperform the low-protein group.

    These findings suggest that resistance training can offset the harmful effects associated with a high-protein diet.

    Current recommendations for protein intake for healthy adults – 0.8 grams per kilogram (0.36 grams per pound) of body weight per day – are likely too low for building and maintaining muscle mass. Doubling the recommended amount, ensuring a daily intake of 1.6 to 1.8 grams per kilogram (0.7 to 0.8 grams per pound) of body weight, will pay the greatest dividends for promoting muscle protein synthesis for non-novices. Learn more about the importance of dietary protein in this episode featuring Dr. Stuart Philips.

  • Advanced glycation end-products (AGEs) form when the sugars, amino acids, and fats in food encounter heat. The molecules in the foods rearrange, forming brown polymers (a process known as the Maillard reaction) and creating the deep flavors of browned barley in beer, roasted coffee, seared meats, and French fries. A recent study in worms shows that dietary AGEs promote overeating and reduce lifespan by as much as 30 percent in those genetically susceptible.

    Researchers investigated the health effects of AGEs in Caenorhabditis elegans, a type of roundworm often used to model human aging. Specifically, they looked at the effects of dietary AGEs derived from methylglyoxal, a byproduct of glycolysis and lipid peroxidation.

    They found that worms lacking the gene for glyoxalase, an enzyme that protects the body from methylglyoxal-derived AGEs, showed increased appetite when exposed to AGEs. They also found that the methylglyoxal-derived AGE known as MG-H1 influences the production of the neurotransmitter tyramine, ultimately contributing to the harmful effects of AGEs, including increased feeding, decreased lifespan, and neuronal damage.

    These findings suggest that dietary AGEs promote overeating and reduce lifespan by as much as 30 percent in genetically susceptible organisms. Although AGEs are present in the diet, they also form in the body during normal glucose metabolism. However, if high AGE levels accumulate in the tissues and blood, they can become pathogenic, driving many chronic diseases, including diabetes, atherosclerosis, Alzheimer’s disease, macular degeneration, and kidney failure. The body clears excess AGEs via the liver (and possibly the kidney)00462-3/fulltext), but the clearance rate declines with age.

    Evidence suggests that a low carbohydrate diet inhibits AGE formation. The ketogenic diet typically restricts carbohydrate intake to roughly 10 percent or less of one’s calories. Learn more about the ketogenic diet and its health effects in this episode featuring Dr. Dominic D'Agostino.

  • Female fertility decreases considerably with age, with nearly 87 percent of women over the age of 45 unable to conceive. However, some evidence suggests that dietary components can preserve fertility. A recent study in mice shows that spermidine, a molecule found in many common foods, including legumes, nuts, and cheese, improves fertility and egg quality.

    Researchers analyzed the ovarian metabolic profiles of young and old mice. Then, they supplemented the aged mice with spermidine and assessed its effects on ovarian function.

    They found that ovarian spermidine levels in older mice were notably lower than in younger mice, correlating with decreased oocyte (egg cell) quality and other indications of ovarian aging. However, administering spermidine to the older mice enhanced follicle development, oocyte maturation, and early embryonic development, thereby boosting the animals' overall fertility. They also found that the older mice exhibited impaired ovarian mitophagy, but spermidine restored it.

    Mitophagy, a form of autophagy, is the selective degradation of mitochondria. It helps ensure that the body’s cells are metabolically efficient, ultimately serving as a trigger for mitochondrial biogenesis, the process of producing new mitochondria. Failures in mitophagy are associated with several chronic diseases, including cardiovascular disease, kidney disease, and Alzheimer’s disease. Learn more about mitophagy and autophagy in our overview article.

  • Maternal exposures during pregnancy can influence the physiology and development of a woman’s child. But scientists aren’t sure whether this influence extends across generations. A new study in worms suggests that consuming ursolic acid – a bioactive compound found in apples and herbs, such as rosemary and sage – during pregnancy promotes the production of key fats in the brain, boosting neuronal health and function in progeny.

    Researchers studied the effects of ursolic acid supplementation in roundworms – a well-established model of human genetics. They fed the worms ursolic acid and assessed its effects on subsequent generations.

    They found that the worms' neural transport processes (similar to synaptic connectivity in vertebrates) were more efficient after consuming ursolic acid. The worms also demonstrated reduced susceptibility to axonal fragility in adulthood. Interestingly, these benefits transcended a singular generation, manifesting within subsequent progeny.

    The mechanism driving these effects centered around the modulation of sphingosine-1-phosphate, a bioactive metabolite of sphingolipid – a type of fat implicated in neural protection. The offspring of worms that consumed ursolic acid demonstrated elevated sphingosine-1-phosphate levels, thereby conveying neural protection across multiple generations.

    These findings suggest that dietary-acquired lipid metabolites can provide neuroprotection across generations. They also underscore the importance of maternal nutrition during pregnancy. Learn about other aspects of maternal (and paternal) health that influence offspring in this clip featuring Dr. Elissa Epel.

  • Kombucha is a fermented beverage made from tea, sugar, bacteria, and yeast. Some evidence suggests that kombucha exerts antimicrobial, antioxidant, detoxifying, and liver-protective effects. A new study has found that kombucha lowers blood glucose levels by nearly 30 percent in people with type 2 diabetes.

    Researchers conducted a small trial involving 12 adults with type 2 diabetes. The participants drank approximately 8 ounces of either kombucha or a placebo beverage daily for four weeks. Eight weeks later, they switched to the other option. During each intervention, they measured their fasting blood glucose levels at the start and after one and four weeks. They completed questionnaires about their overall health, insulin needs, gut health, skin condition, and mental state. The researchers analyzed the kombucha’s microbiota and quantified its fermentation products.

    When the participants drank the kombucha, they experienced a notable drop in average fasting blood glucose levels by the end of the intervention compared to the start (164 versus 116 mg/dL – nearly 30 percent lower). However, the placebo group did not experience the same reduction (162 versus 141 mg/dL – less than 13 percent lower). The microbiota analysis revealed lactic acid bacteria, acetic acid bacteria, and yeast as the dominant components. The primary fermentation products were lactic acid, acetic acid, and ethanol.

    This was a very small study, but the findings suggest that kombucha might have blood glucose-lowering potential for people with diabetes. Learn how consuming fermented foods, such as kombucha, kefir, and others, increases gut microbial diversity and decreases inflammation in this clip from a live Q&A with Dr. Rhonda Patrick.

  • Maternal nutrition during pregnancy plays a critical role in a child’s development. A new study suggests that low dietary fiber intake during pregnancy harms neurodevelopment. Children of women who consumed lower levels of dietary fiber during pregnancy were nearly 50 percent more likely to experience developmental delays.

    The study involved more than 76,000 Japanese mother-infant pairs. The women completed questionnaires about their typical dietary intake and supplement use during their pregnancies and then provided information about their child’s development at the age of three years.

    The questionnaires revealed that, on average, the women consumed roughly 10 grams of fiber daily during their pregnancies, far less than the 18 grams recommended for pregnant women according to the Dietary Reference Intakes for Japanese. Children of women with the lowest fiber intake were approximately 50 percent more likely to experience difficulties with communication, fine motor skills, and problem-solving and 30 percent more likely to experience problems with personal-social skills than children of women with the highest intake.

    Dietary fiber is a broad term for the non-digestible components of plant-based foods. According to the Dietary Guidelines for Americans, the recommendations for combined fiber intake vary according to age and sex. Women need between 22 and 28 grams of fiber daily, and men need between 28 and 34 grams daily. Pregnant women need at least 28 grams of fiber daily. Most people in the United States only get about half the recommended amount of fiber.

    These findings suggest that lower dietary fiber intake during pregnancy harms fetal neurodevelopment. The mechanisms driving this association may be related to dietary fiber’s role in modulating the gut microbiota. Studies in mice suggest that dysbiosis – an imbalance in the microbes that inhabit the gut – impairs development and [promotes gut inflammation[(https://pubmed.ncbi.nlm.nih.gov/34879222/) in offspring. Learn more about the role the gut microbiota plays in health in this episode featuring Dr. Eran Elinav.

  • Hip fractures can lead to a decline in self-reliance, diminished quality of life, and feelings of depression. However, some research suggests that consuming fish and omega-3 fatty acids influences a person’s risk of experiencing a hip fracture. A 2019 meta-analysis and systematic review found that higher fish and omega-3 intake reduces the risk of hip fracture by as much as 12 percent.

    Researchers reviewed the findings of 10 studies involving nearly 300,000 people. Seven of the studies followed people over time (prospective), and three compared groups with and without fractures (case-control).

    They found that people who consumed more fish had a lower risk of hip fractures, even when combining the results from prospective and case-control studies. They found the same protective effect for those who consumed higher omega-3s in their diets. Notably, the protective effect of fish and omega-3 intake remained only when considering larger prospective studies (involving 10,000 participants or more) or studies that included body mass index as a factor.

    These findings suggest that dietary intake of fish and omega-3s might promote bone health and reduce the risk of hip fractures. Other studies have proposed mechanisms by which omega-3s exert their beneficial effects. For example, one study found that DHA inhibits osteoclast formation and subsequent bone resorption by inhibiting the production of TNF-alpha, a pro-inflammatory molecule. A separate study demonstrated that resolvin, a byproduct of omega-3 metabolism, promotes bone preservation under inflammatory conditions and influences the PI3K-AKT pathway, a major signaling pathway implicated in many human diseases, including osteoporosis.

  • Older adults with hearing loss are more likely to experience cognitive decline and an increased risk of developing dementia. However, a new study suggests that hearing aids can moderate this risk. Older adults with hearing loss who wore hearing aids were nearly half as likely to develop dementia as those who didn’t.

    Researchers recruited nearly 1,000 older adults aged 70 to 84 with untreated hearing loss. About half of the participants received hearing aids, and the other half received health education counseling. The researchers assessed the participants' cognitive function every six months for three years.

    They found no difference in cognitive decline between the two groups when considering the entire cohort. However, when they looked at specific subgroups, they found that the effect of hearing aids on cognitive change varied according to the participants' risk profiles. Specifically, hearing aids appeared to reduce cognitive change in older adults with a higher risk of decline but not in those with a lower risk.

    These findings suggest that hearing aids benefit older adults with a higher risk of cognitive decline. Approximately two-thirds of all adults over 70 have some degree of hearing loss. Evidence suggests that adhering to healthy dietary patterns such as the DASH diet or the Mediterranean diet reduces the risk of mild hearing loss by nearly 30 percent, highlighting potential links between diet, dementia, and hearing loss. Learn more about dietary strategies to reduce the risk of dementia in this episode featuring Dr. Dale Bredesen.

  • Traditional weight-loss programs typically emphasize calorie restriction – often cited as the primary reason participants drop out. But time-restricted eating is a weight loss strategy that limits one’s daily eating window to a specific period without focusing on restricting calories. A new study found that time-restricted eating was as effective as calorie restriction for weight loss.

    The study included 90 adults with obesity who followed one of three dietary patterns for a year: time restriction, calorie restriction, and no restriction (a control group). The time-restricted group ate during an eight-hour window, from noon to 8:00 p.m., without limiting calories. The calorie-restricted group cut their calories by 25 percent. The control group ate during a 10-hour (or more) window and did not change their diets. Researchers assessed the participants' body weights, metabolic markers, and caloric intake throughout the study.

    They found that the time-restricted and calorie-restricted groups experienced considerable weight loss compared to the control group by the end of the year. The time-restricted group lost more than 10 pounds (~4.8 percent of their body weight), while the calorie-restricted group lost nearly 12 pounds (~5.3 percent). There was no statistically significant difference in weight loss between the two groups. Notably, the control group averaged a 2.4-pound weight gain over the year.

    These findings suggest that time-restricted eating is as effective for weight loss as calorie restriction. In this study, the eating window began around noon – often described as a “late” window. However, some evidence indicates that an early eating window is more beneficial than a later one. Learn more about time-restricted eating in this episode featuring Dr. Satchin Panda.

  • The role of Vitamin K1 in blood clotting is well established. However, a new study shows that higher vitamin K1 intake may also reduce the risk of type 2 diabetes. People with higher K1 intake were more than 30 percent less likely to develop type 2 diabetes than those with lower intake.

    Researchers tracked the health and dietary intake of nearly 55,000 adults for approximately 20 years. Then they used statistical analysis to identify links between vitamin K1 intake and the risk of type 2 diabetes.

    They found that people with the highest vitamin K1 intake were 31 percent less likely to develop type 2 diabetes than those with the lowest intake, even after considering other risk factors. The association between vitamin K1 intake and reduced diabetes risk was particularly robust in men, smokers, and those who were overweight or sedentary.

    These findings suggest that eating vitamin K1-rich foods reduces the risk of developing type 2 diabetes. They also highlight a potential synergistic effect for the two forms of vitamin K, based on recent research demonstrating vitamin K2’s effects on maintaining glycemic control in people with type 2 diabetes.

    Vitamin K is a fat-soluble vitamin. Naturally occurring forms of vitamin K include phylloquinone (vitamin K1) and a family of molecules called menaquinones (vitamin K2). Vitamin K1 is synthesized by plants and is the major form found in the diet. Vitamin K2 molecules are synthesized by the gut microbiota and found in fermented foods and some animal products (especially liver).

  • The list of health attributes of broccoli includes anticancer, antioxidant, and anti-diabetes effects, as well as many others. Now a new study in mice shows that eating broccoli protects the gut. Molecules in broccoli interact with proteins present in the small intestine, increasing the number of cells involved in safeguarding the gut.

    Researchers fed one group of mice a diet containing 15 percent freeze-dried broccoli – roughly equivalent to 3.5 cups of fresh broccoli in the human diet. They fed another group their typical food, which included no broccoli. Then they examined the animals' small intestines to assess the effects of broccoli consumption on the gut.

    They found that molecules in the broccoli – likely phytochemicals, microbiota, or byproducts of metabolism – bound with specific proteins in the gut called aryl hydrocarbon receptors. Subsequently, the number of goblet and Paneth cells in the animals' guts increased. Goblet cells produce mucus, which protects and lubricates the gut to facilitate the passage of food. Paneth cells produce antimicrobial peptides and immune factors that regulate the gut microbial composition.

    These findings suggest that broccoli consumption protects the gut via interaction with the aryl hydrocarbon receptor. Broccoli is a rich source of phytochemicals, including sulforaphane, an isothiocyanate compound with potent antioxidant, anticancer, and anti-inflammatory properties. Learn more about sulforaphane in this episode featuring Dr. Jed Fahey.

  • Previous research has shown that creatine supplementation increases bone mass. But a recent trial in postmenopausal women found that creatine had little effect on bone mineral density. It did, however, improve aspects of bone quality.

    Researchers studied the effects of creatine monohydrate supplementation on the bone health of 237 postmenopausal women. Half of the participants took creatine (0.14 grams per kilogram of body weight of creatine, ~10 grams for a 160-pound female) daily for two years, while the other half took a placebo. All the participants engaged in a walking and resistance training exercise program. The researchers measured the women’s bone mineral density and other aspects of bone before and after the two-year intervention.

    They found that the creatine supplements had no significant effects on the women’s bone mineral density of the femoral neck, total hip, or lumbar spine compared to the placebo. However, creatine did improve aspects of their bone quality. Women who took creatine showed improvements in the section modulus (how resistant the bone is to bending and breaking) and the buckling ratio (how well the bone can withstand compression and maintain its shape without collapsing) at the narrow part of the femoral neck.

    Creatine is a nitrogen-containing compound that is produced in the liver and kidneys and is stored in the brain and muscles. It plays essential roles in the recycling of ATP and is widely used as a dietary supplement to build and maintain muscle mass.

    These findings suggest that supplemental creatine in conjunction with exercise did not affect bone mineral density in postmenopausal women, but it did improve certain aspects of bone quality. However, robust data support resistance training as a means to build bone mass. Learn more in this episode featuring Dr. Brad Schoenfeld.

  • Nutrition experts have long known that olive oil, which is rich in antioxidants and bioactive compounds, provides protection against cardiovascular disease. But a recent review suggests that the beneficial effects of olive oil extend to maternal and fetal health, too. Pregnant women who consumed more olive oil were less likely to develop pregnancy-related complications, and their infants were more likely to have healthy weights than those who consumed less.

    Researchers analyzed the findings of nine studies investigating the effects of olive oil on maternal and fetal outcomes. More than 44,000 women participated in the various studies.

    The researchers found that a higher intake of olive oil was associated with a lower risk of gestational diabetes, preeclampsia, and pregnancy-related cardiovascular complications. Higher intake was also associated with a lower risk of an infant being small for gestational age (which increases the risk of infant mortality) or large for gestational age (which increases the risk of birth complications).

    Nutrition plays an important role in prenatal health, and these findings suggest that olive oil can play a role in protecting both moms and babies during pregnancy. Other evidence suggests that omega-3 fatty acids may even prevent pre-term birth. Learn more in this clip featuring Dr. Bill Harris.

  • Higher intake of omega-3 fatty acids may reduce the risk of breast cancer, a 2022 study found. Women with the highest omega-3 intake were as much as 49 percent less likely to develop breast cancer than those with the lowest intake.

    Researchers conducted a study that included more than 3,200 women, roughly half of whom had breast cancer. The women provided information about what they typically ate, including foods rich in omega-3 fatty acids, and whether they were pre- or postmenopausal.

    The researchers found that a higher intake of omega-3 in the form of alpha-linolenic acid reduced breast cancer risk by 49 percent; a higher intake in the form of eicosapentaenoic acid reduced risk by 32 percent. The links between omega-3s and breast cancer risk were strongest among premenopausal women and women with hormone-sensitive tumors. Interestingly, higher omega-3 intake markedly reduced the risk of breast cancer among women who had obesity or overweight but not among those who had healthy weights.

    These findings suggest that omega-3s reduce the risk of breast cancer, the second leading cause of cancer-related death among women. Inflammation plays a key role in the pathogenesis of many cancers, including breast cancer. Learn how omega-3 fatty acids reduce inflammation in this clip featuring Dr. Bill Harris.

  • A 2018 study found that supplemental magnesium reduced levels of C-reactive protein (CRP) – a robust marker of inflammation. Improvements in CRP levels were seen regardless of the dose or duration of supplementation.

    Researchers analyzed the findings of eight randomized, controlled trials that investigated the effects of supplemental magnesium on CRP.

    They found that doses ranged from 320 to 1,500 milligrams per day, and the duration of supplementation ranged from eight hours to just over six months. CRP levels dropped an average of 1.33 milligrams per deciliter (mg/dL) with magnesium supplementation, especially when CRP levels were 2.0 mg/dl or higher. Because normal CRP levels (seen in most healthy adults) are typically less than 0.3 mg/dL and normal or slightly elevated levels are typically 0.3 to 1.0 mg/dL, this reduction represented a considerable change.

    C-reactive protein is a protein that increases up to 1,000-fold at sites of inflammation or infection in response to elevated levels of inflammatory cytokines, especially interleukin-6. It can also increase in the blood following a heart attack, surgery, or trauma. High CRP levels are associated with atherosclerosis, congestive heart failure, atrial fibrillation, and myocarditis, suggesting that CRP participates in the pathophysiology of cardiovascular disease.

    Magnesium is an essential mineral. It is found in green leafy vegetables, whole grains, legumes, and nuts. Poor magnesium status is implicated in several metabolic and inflammatory disorders including hypertension, type 2 diabetes, metabolic syndrome, insulin resistance, and cardiovascular diseases.

    The findings from this meta-analysis suggest that supplemental magnesium reduces inflammation, a driver of many chronic diseases. You can read about other strategies to reduce inflammation in our overview articles on aerobic exercise, sauna use, and cold exposure.

  • Magnesium may protect the brain from age-related volume losses, a new study showed. People with the highest magnesium intake had larger brain volumes than those with lower intake – a protective effect that corresponded to roughly one year less aging.

    The study involved more than 6,000 adults between the ages of 40 and 73 years enrolled in the UK Biobank study. The participants completed questionnaires about their typical daily magnesium intake. They also underwent brain scans that measured their brain volumes and identified the presence of white matter lesions – areas in the brain that often indicate cerebral small blood vessel disease, a risk factor for dementia.

    The scans revealed that participants with the highest magnesium intake – 550 milligrams or more daily – had larger gray matter and hippocampal volumes than those with normal intake (about 350 milligrams daily). In middle-aged adults, this effect on brain health corresponded to about one year of aging. The protective effects of magnesium were more pronounced in women than in men.

    Magnesium is an essential mineral. It is found in green leafy vegetables, legumes, nuts, seeds, and whole grains, and is widely available as a dietary supplement. Evidence suggests that low magnesium levels are involved in the pathogenesis of various age-related brain disorders. In addition, people with Alzheimer’s disease often have lower magnesium levels than healthy people. More than half of people living in the United States likely have magnesium deficiency

    These findings suggest that magnesium protects the brain against age-related volume losses, which are associated with dementia. It also aligns with other research showing that people who follow the MIND diet, which emphasizes the consumption of magnesium-rich green leafy vegetables, were 40 percent less likely to develop Alzheimer’s disease.

  • Eating a Mediterranean-style diet may reduce dementia risk. A new study shows that eating a Mediterranean-style diet reduces the risk of dementia. Older adults with higher adherence to a Mediterranean-style diet were 23 percent less likely to develop dementia than those with lower adherence.

    The study involved more than 60,000 adults enrolled in the UK Biobank study. Researchers scored the participants' adherence to the Mediterranean Diet based on reports of their normal dietary intake. They estimated each participant’s genetic risk for dementia and reviewed their medical records to learn if they had been diagnosed with dementia over a period of roughly nine years.

    They found that higher adherence to a Mediterranean-style diet was linked with a 14 to 23 percent lower risk of developing dementia during the study period. Interestingly, they did not identify an interaction between adherence to a Mediterranean-style diet and the participants' genetic risk for dementia, suggesting that eating a healthy diet could reduce the risk of developing dementia even among those who are genetically predisposed to the condition.

    The Mediterranean Diet is a dietary pattern that emphasizes fruits, vegetables, whole grains, legumes, and healthy fats, such as those in nuts, avocados, and olives. Evidence suggests that the healthy fats in salmon and their roe (eggs) protect the brain against cognitive decline. Learn more about the health benefits of salmon roe in our overview article.

  • People who followed the MIND or Mediterranean Diets had fewer amyloid plaques and tau tangles – hallmarks of Alzheimer’s disease – in their brains than those who didn’t, according to a new study. They were also 40 percent less likely to develop Alzheimer’s disease.

    The study involved nearly 600 adults who agreed to postmortem examination of their brains. Researchers scored the participants' adherence to the two dietary patterns over a period of approximately seven years and analyzed the effects of specific dietary components on brain health.

    They found that the brains of people who closely adhered to either of the two diets had fewer signs of Alzheimer’s disease – specifically, amyloid-beta load, phosphorylated tau tangles, and global Alzheimer’s disease pathology – than those who didn’t, even after considering the participants' physical activity levels, smoking status, and vascular disease burden. Those who closely followed the diets were also 40 percent less likely to develop the disease over a period of, on average, about seven years. Green leafy vegetables stood out as having the greatest beneficial influence on brain health and Alzheimer’s disease pathology.

    The Mediterranean Diet emphasizes the consumption of vegetables, fruits, legumes, healthy fats, and at least three servings of fish weekly. The MIND diet, which is short for Mediterranean-DASH Intervention for Neurodegenerative Delay, recapitulates aspects of the Mediterranean Diet and the DASH diet, with an emphasis on the consumption of green leafy vegetables, berries, and at least one serving of fish weekly. Both the MIND and Mediterranean diets permit small amounts of wine daily.

    These findings suggest that the MIND and Mediterranean Diets confer protection against Alzheimer’s disease. Learn about other strategies to prevent Alzheimer’s disease in this episode featuring Dr. Dale Bredesen.

  • People who follow vegan diets generally have weaker bones than omnivores, a new study shows. However, vegans and omnivores who practice resistance training have comparable bone strength.

    The study included 88 healthy adults. About half had followed a vegan diet for five years or more, while the other half had followed an omnivorous diet. Participants provided information about their dietary intake and exercise practices, and researchers assessed their bone microarchitecture – a measure of bone strength.

    They found that, overall, vegans had altered microarchitecture compared to omnivores. However, the bone microarchitecture of vegans and omnivores who practiced resistance training was comparable, suggesting that resistance exercise compensated for dietary differences between the two groups. Interestingly, aerobic exercise alone did not confer a protective effect on bone microarchitecture.

    These findings suggest that resistance training protects against bone loss associated with vegan diets. Aerobic exercise did not appear to confer protection, however.

    Vegan diets are rich in plants and plant-based proteins. People who follow vegan diets often experience more bone loss over time than those who follow an omnivorous diet. Evidence suggests that plant-based proteins – when consumed in sufficient quantities – can support muscle hypertrophy in resistance training, which would in turn support bone health. Learn more in this episode featuring Dr. Stuart Phillips.

  • A new study shows that eating wild blueberries, which are rich in bioactive compounds called anthocyanins, may improve athletic performance. After young men consumed freeze-dried wild blueberries for two weeks, their fat oxidation rates during exercise increased by more than 43 percent.

    During exercise, fats and carbohydrates undergo oxidation, providing fuel for contracting muscles. At lower exercise intensity, the body relies primarily on fat oxidation; at higher intensity, the body shifts more toward carbohydrate oxidation. During endurance training, the body’s carbohydrate stores can deplete, causing fatigue and impairing athletic performance.

    The study involved 11 healthy, aerobically fit men. The men ate 25 grams of freeze-dried wild blueberry powder (roughly equivalent to a cup of fresh blueberries and providing 325 grams of anthocyanins) every day for two weeks. Before and after the intervention, researchers measured men’s fat utilization at 65 percent of their peak oxygen consumption while exercising.

    They found that the men’s fat oxidation increased by 19.7 percent after exercising for 20 minutes, 43.2 percent after 30 minutes, and 31.1 percent after 40 minutes. Conversely, their carbohydrate oxidation decreased by 10.1 percent after 20 minutes, 19.2 percent after 30, and 14.8 percent after 40. The men’s lactate levels were lower, too, likely due to improved blood flow.

    Anthocyanins are polyphenolic compounds that exert antioxidant, anti-inflammatory, and cardioprotective effects, among others. It’s noteworthy that freeze-drying blueberries induces considerable anthocyanin losses. Eating fresh blueberries may provide even greater benefits to athletic performance.

    The findings from this small study suggest that consuming anthocyanin-rich blueberries promotes fat oxidation, thereby enhancing athletic performance. Further studies in larger populations are needed to confirm these effects.

  • According to a new study in teens, higher dietary protein intake improves mood. Adolescent athletes who ate more protein in their diets experienced fewer symptoms of depression.

    The study involved 97 adolescent athletes who reported their depressive symptoms before and after a span of 10 months. About three months into the study period, they completed a three-day diary of their typical dietary intake.

    The food diaries revealed that, in general, the teens ate fewer healthy fats and carbohydrates than recommended, but more sugar than recommended. Their dietary protein intake met recommendations but was typically lower among females than males. Teens that ate higher amounts of protein were less likely to report depressive symptoms than those with lower intake.

    Dietary protein is essential for human health. It provides the building blocks for many biological components, including neurotransmitters in the brain, which play crucial roles in mood, sleep, appetite, and other physiological processes. Although this study did not assess the teens' athletic performance, it’s important to note that protein supports muscle growth and maintenance, ultimately influencing aspects of performance. Learn more about the importance of dietary protein in this episode featuring Dr. Philip Stuart.

  • Eating more fiber may reduce the risk of severe headaches or migraines, a recent study shows. For every 10 grams of dietary fiber consumed, the risk of severe headache or migraine decreased by 11 percent.

    The study involved nearly 13,000 people living in the United States. Participants provided information about their regular dietary fiber intake and the number and severity of their headaches or migraines.

    People who consumed the highest amount of dietary fiber (more than 22 grams per day) were 26 percent less likely to report experiencing severe headaches or migraines than those who consumed the least amount of fiber (less than 7.8 grams per day). For every 10-gram per day increase in dietary fiber intake, the frequency of severe headaches or migraines dropped by 11 percent.

    Dietary fiber refers to the indigestible components of plant-based foods. The fermentation of dietary fibers in the gut produces molecules that modulate immune function by way of T regulatory cells, such as the short-chain fatty acids.

    According to the Dietary Guidelines for Americans, the recommendations for combined fiber intake vary according to age and sex. Women need between 22 and 28 grams of fiber per day, and men need between 28 and 34 grams per day. Most people living in the United States only get about half of the recommended amounts of fiber daily.

    The findings of this study suggest that consuming dietary fiber protects against severe headaches and migraines. Obtaining enough fiber when following a ketogenic diet may prove challenging. Learn how to include fiber in a ketogenic diet in this episode featuring Dr. Dominic D'Agostino.

  • A new small study shows that drinking a fermented dairy beverage improves memory in healthy adults. People who consumed kefir exhibited improvements in relational memory – the capacity to remember associations between objects, places, people, or events, such as associating a name with a face.

    The study involved 26 healthy young adults. About half of the participants consumed an 8-ounce serving of kefir (a yogurt-like probiotic drink) daily for four weeks, while the other half consumed an 8-ounce serving of low-fat, lactose-free milk. After a two-week washout period, the two groups switched beverages for an additional four weeks. Researchers assessed the participants' relational memory, mood, and microbiota composition before and after each intervention.

    They found that participants who consumed the kefir showed improvements in their relational memory. In addition, the number of Lactobacillus bacteria in their guts increased by 235 percent. However, the researchers did not identify any associations between microbiota changes and memory performance or mood, a finding that may have been related to the small study size, according to the study’s authors.

    Lactobacillus bacteria are among the most abundant bacterial species in the human gut. They are commonly referred to as “good bacteria” due to their beneficial effects on human health, particularly that of the gut. Learn about Lactobacillus reuteri, a type of Lactobacillus that strengthens the gut barrier, reducing leakiness and potentially influencing brain health.

  • Skipping breakfast may impair immune function.

    Skipping breakfast adversely affects immune health, a new study in mice shows. Mice that skipped breakfast experienced a 90 percent drop in white blood cell numbers and demonstrated impaired immune function.

    Researchers investigated the effects of fasting on immune health in two groups of mice. One group of mice ate breakfast upon waking, while the other group fasted, skipping breakfast. The researchers measured white blood cell numbers immediately after both groups of mice woke up and at four and eight hours after waking. Then they infected the mice with a type of bacteria that commonly causes pneumonia to see how their immune systems responded.

    They found that after just four hours, the white blood cell numbers in the blood of fasting mice decreased by 90 percent, having accumulated in the bone marrow. Upon refeeding, the number of white blood cells in circulation increased markedly, and most of these cells were older and exhibited pro-inflammatory characteristics. After exposure to the pneumonia-causing bacteria, the mice that fasted were more likely to die (and died sooner) than the mice that didn’t fast.

    These findings suggest that skipping breakfast during fasting impairs immunity. They also align with evidence that an earlier eating window when practicing time-restricted eating (which involves a long overnight fast) is more beneficial](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8634676/) than a later one. Learn more about time-restricted eating in this episode featuring Dr. Satchin Panda.](https://www.foundmyfitness.com/episodes/satchin-panda-3)

  • Using a salt substitute helps reduce blood pressure, a 2022 review found. Swapping salt with a salt substitute dropped systolic blood pressure by nearly 5 mmHg and reduced the risk of premature death.

    Researchers reviewed the findings of 23 randomized controlled trials involving more than 32,000 people with high blood pressure. The various trials investigated the effects of switching sodium-based salt with a potassium-based salt substitute on blood pressure, urinary output of sodium and potassium, and the risk of premature death from cardiovascular disease and other causes.

    They found that, on average, using a salt substitute reduced systolic blood pressure by 4.80 mmHg and diastolic blood pressure by 1.48. As expected, urinary output of sodium decreased considerably, while urinary out of potassium, which exerts robust blood pressure-lowering effects, increased. Using a salt substitute reduced the risk of dying from all causes of premature death by 12 percent.

    Other research has shown that a 5-mmHg reduction of systolic blood pressure reduces the risk of major cardiovascular events by about 10 percent. When combined with other lifestyle behaviors, such as exercising, maintaining a healthy weight, and sauna use, using a potassium-based salt substitute is a promising, non-pharmacological approach to reducing blood pressure.

  • Eating a Mediterranean-style diet, which is abundant in polyphenol-rich fruits, vegetables, olive oil, legumes, and nuts, helps reduce abdominal fat, a 2022 study found. People who followed a Mediterranean-style diet supplemented with a polyphenol-rich shake for 18 months lost twice as much abdominal fat as those who consumed a lower-polyphenol diet.

    Researchers assigned nearly 300 people to follow one of three diets plus exercise: a Mediterranean-style diet that included walnuts; a Mediterranean-style diet that included walnuts, green tea, and a shake that contained duckweed (a polyphenol-rich aquatic plant native to Asia); and a diet that adhered to conventional healthy dietary guidelines. They measured the participants' body weight and waist circumference and conducted magnetic resonance imaging (MRI) studies to assess their abdominal fat at the beginning and end of the intervention.

    They found that participants who followed the two variations of the Mediterranean/walnut diets lost body weight and their waist circumferences decreased, compared to those who followed the healthy dietary guidelines. However, MRIs revealed that while those who followed the Mediterranean/walnut diet lost 6.0 percent of their abdominal fat, those who followed the Mediterranean/walnut diet that included tea and duckweed lost 14.1 percent of their abdominal fat – more than twice as much.

    Walnuts are rich in the polyphenolic compound ellagic acid. Bacteria in the human gut break down ellagic acid to produce urolithins. Scientists have identified about 20 urolithins, but the most studied of these is urolithin A, which exerts potent anti-obesity effects.

    Duckweed is rich in polyphenols, carotenoids, omega-3 fatty acids, fiber, and many micronutrients, including iron and vitamin B12. The polyphenols in duckweed exert robust antioxidant activity and support healthy blood glucose levels – critical elements in maintaining healthy body weight and waist circumference.

  • Higher blood levels of antioxidant compounds called carotenoids may lower a person’s risk of having high blood pressure, a 2022 study found. The greatest risk-lowering benefit was seen with the carotenoid compound beta-carotene, which cut the risk of having high blood pressure in half.

    The study involved more than 11,000 adults enrolled in NHANES, an ongoing assessment of the health and nutritional status of people living in the United States. Researchers measured the levels of six carotenoids (alpha-carotene, beta-cryptoxanthin, lutein/zeaxanthin, trans-lycopene, trans-beta-carotene, and cis-beta-carotene) in the participants' blood and took their blood pressures.

    They found that having higher levels of all six of the carotenoids markedly reduced the risk of having high blood pressure. However, trans-beta carotene reduced the risk by 50 percent, and cis-beta-carotene reduced the risk by 53 percent.

    Carotenoids are antioxidant compounds naturally present in many red, yellow, or orange fruits and vegetables. Beta carotene is found in carrots, sweet potatoes, and winter squash. Epidemiological data suggest that consumption of carotenoid-rich foods reduces the risk of many diseases, including type 2 diabetes, macular degeneration, and prostate cancer.

  • From the publication:

    Per- and polyfluoroalkyl substances (PFAS), previously referred to as “perfluorinated compounds”, are a class of manufactured chemicals that have been detected in nearly all sampling of geographic locations and environmental matrices worldwide, including sites that had no nearby manufacture or use of PFAS. PFAS are used in hundreds of industrial and consumer products including food packaging and waterproof/stain resistant fabrics. Their strong carbon-fluorine bonds provide both hydrophobic and oleophobic properties, which make these chemicals extremely persistent in the environment. The class of PFAS includes tens of thousands of potential environmental contaminants including over one thousand chemicals previously or currently approved for use in the U.S..

    For PFAS measured at concentrations already found in the general population, exposure may suppress the immune system. Additionally, exposure to PFAS, with most studies on PFOA and PFOS, has been associated with many health harms, including an increased risk of cancer, high cholesterol, thyroid disease, and reproductive and developmental harms.

    The median level of total targeted PFAS in fish fillets from rivers and streams across the United States was 9,500 ng/kg, with a median level of 11,800 ng/kg in the Great Lakes. PFOS was the largest contributor to total PFAS levels, averaging 74% of the total. The median levels of total detected PFAS in freshwater fish across the United States were 278 times higher than levels in commercially relevant fish tested by the U.S. Food and Drug Administration in 2019–2022. Exposure assessment suggests that a single serving of freshwater fish per year with the median level of PFAS as detected by the U.S. EPA monitoring programs translates into a significant increase of PFOS levels in blood serum.

    Additional information:

    In June 2018, the Agency for Toxic Substances and Disease Registry (ATSDR) released a draft Toxicological Profile that derived minimal risk levels (MRLs), which are similar to RfDs, for intermediate duration exposure (15–364 days) of four PFAS routinely measured in NHANES [28]. The MRL [minimal risk levels] values for PFOA (3 ng/kg/day) and PFOS (2 ng/kg/day) are 6.7 and 10 times lower than the RfDs EPA used to develop its 2016 HAs and similar to those developed by New Jersey, though they are based on different studies and endpoints. View full publication

  • Extra virgin olive oil boosts brain function and halts the effects of aging on the brain, a 2019 study in mice found. Mice that ate an olive oil-rich diet had fewer abnormal deposits of tau – a protein associated with Alzheimer’s disease – in their brains and performed better on memory tests than mice that didn’t eat olive oil.

    Researchers fed mice that are predisposed to developing abnormal tau deposits in their brains an olive oil-enriched diet or their regular chow from young adulthood to older adulthood. They subjected the mice to various cognitive tests and then they examined the animals' brains for the presence of abnormal tau deposits.

    They found that the mice that ate the olive oil-rich diet had approximately 60 percent fewer abnormal tau deposits than mice that ate regular chow. The olive oil-eating mice also demonstrated enhanced hippocampal synaptic activity, short-term plasticity, and memory.

    Olive oil is rich in bioactive compounds, including polyphenols, carotenoids, oleic acid, and others. Olive oil is a fundamental component of the Mediterranean diet, which is associated with a wide range of health benefits, including reduced incidence of Alzheimer’s disease.

    This study in mice suggests that olive oil reduces the risk of abnormal changes in the brain associated with Alzheimer’s disease. Diets rich in omega-3 fatty acids may have beneficial effects on brain health, too. Learn more in our omega-3 overview article.

  • Exposure to a dye found in many commonly consumed foods may increase the risk of developing inflammatory bowel diseases, a new study finds. The dye impairs gut barrier function and increases serotonin production, altering the gut microbiota.

    Researchers fed mice either normal mouse chow or mouse chow that contained a red food dye called Allura Red for 12 weeks and assessed their gut health. Allura Red, also known as FD&C Red 40 or Food Red 17, is used in many food products, including candy, soft drinks, dairy products, and some breakfast cereals.

    The researchers found that exposure to the dye when the mice were young heightened the animals' susceptibility to colitis (a type of inflammatory bowel disease) later in life. Mice that developed colitis had higher gut serotonin levels and impaired gut barrier function.

    Elevated gut serotonin promotes gut inflammation and is a common feature of inflammatory bowel diseases. Impaired gut barrier function drives intestinal permeability (also known as “leaky gut”) – a condition in which gaps form between the cells that line the gut. Intestinal permeability allows pathogens to leak through the intestinal barrier and pass directly into the bloodstream, promoting inflammation.

    The findings from this study suggest that exposure to a commonly used food additive increases the risk of developing inflammatory bowel disease by promoting intestinal permeability. Read more about intestinal permeability in our overview article.

  • A compound present in broccoli sprouts may help you sleep better at night, a new study shows. People who consumed glucoraphanin – a bioactive compound found in broccoli sprouts that is a precursor to sulforaphane – slept better and had lower inflammatory markers than those who didn’t take the compound.

    Researchers conducted a small, randomized, placebo-controlled trial involving 18 healthy adults. Twelve of the participants took 30 milligrams of glucoraphanin daily for four weeks while the remaining six took a placebo. The participants wore sleep monitors and reported their sleep quality. The researchers measured the participants' melatonin and inflammatory markers.

    They found that the participants who took the glucoraphanin experienced better sleep quality than those who took the placebo. They also had higher blood concentrations of melatonin and lower levels of prostaglandin D2, a pro-inflammatory mediator.

    Melatonin is a hormone produced deep within the brain, in the pineal gland. It is a key player in the body’s circadian metabolic processes and serves as the body’s natural sleep inducer. Melatonin production may be impaired in a pro-inflammatory state, and increased oxidative stress and inflammation may reduce sleep quality.

    Glucoraphanin is found in certain cruciferous vegetables, including broccoli (especially broccoli sprouts) and red kale. Glucoraphanin is hydrolyzed by the enzyme myrosinase to produce sulforaphane, which demonstrates many beneficial effects in humans. Learn more about the health effects of sulforaphane in this live Q&A featuring Dr. Jed Fahey.

  • From the article:

    Misra compared 109 female athletes with exercise-induced menstrual irregularities with 50 female athletes with normal menstrual cycles and 39 female non-athletes. All of the study subjects were 14-25 years old and were in a normal weight range. The young women’s eating behavior and mental health was evaluated with self-report assessments and questionnaires.

    Athletes with irregular periods reported a higher drive for thinness and more mental control over their food intake compared with athletes with regular periods and non-athletes. They also had higher mean body dissatisfaction scores than athletes with regular periods.

    Athletes who had irregular menstrual periods were randomly assigned to receive either estrogen replacement through a patch, at a dose that resulted in estrogen levels seen with normal menstrual cycles; a commonly used combined oral contraceptive pill containing estrogen; or no estrogen for 12 months. Athletes randomized to estrogen replacement as a patch also received cyclic progesterone.

    Over one year, the groups that received estrogen showed reductions in drive for thinness, body dissatisfaction and uncontrolled eating, compared with those who didn’t receive estrogen. The patch was the most effective, leading to significant decreases in body dissatisfaction and uncontrolled eating.

    View full publication

  • Consuming honey improves blood glucose and cholesterol levels, a recent analysis shows. Raw, unprocessed honey from a single floral source provides the greatest health benefits.

    Researchers reviewed the findings of 18 studies that investigated the effects of honey consumption on various cardiometabolic risk factors, including body fat, glucose levels, blood lipids, blood pressure, inflammatory markers, and others. They also noted the effects of processing and sourcing on honey’s effects.

    They found that honey lowered fasting blood glucose, LDL (“bad”) cholesterol, and triglycerides and increased HDL (“good”) cholesterol and some markers of inflammation. Raw honey – which is unprocessed – had the greatest beneficial effects, especially if it was from a single source, particularly black locust or clover.

    Honey is a complex mixture of sugars, enzymes, proteins, minerals, vitamins, and other bioactive substances that exert antioxidant, antibacterial, and antiseptic effects in humans. Evidence suggests that honey benefits cardiovascular, metabolic, neurologic, and gastrointestinal health.

    These findings demonstrate that, despite its naturally high sugar content, honey differs from other natural sweeteners and may benefit cardiometabolic health. Refined sugar, on the other hand, has profound, negative effects on the human body. Learn more in this episode featuring Dr. Rhonda Patrick.

  • A high-fat, high-sugar diet accelerated normal vascular aging in mice, according to a 2021 study. However, regular, lifelong aerobic exercise maintained vascular health and ameliorated some of the harmful effects of a poor diet.

    Researchers studied the effects of diet and exercise on cardiovascular health in mice that exhibit many of the key features of age-related vascular dysfunction in humans. Starting at the age of three months and continuing until their natural deaths, half of the mice ate a normal diet, while the other half ate a diet that was high in fat and sugar and low in dietary fiber – much like the typical Western diet. Because mice voluntarily run in the wild and in captivity, half of each group of mice was allowed access to a running wheel for exercise, while the other mice were sedentary.

    The researchers found that as the mice aged, they exhibited signs of declining cardiovascular health. In particular, they exhibited impaired endothelium-dependent dilation, a condition that occurs in the early stages of vascular disease and is a precursor to atherosclerosis. This effect was exacerbated by the high-fat/high-sugar diet. However, the researchers found that exercise ameliorated some of the harmful vascular effects of the high-fat/high-sugar diet throughout the lifespan, likely due to lower levels of oxidative stress and inflammation.

    This study in mice demonstrates that aerobic exercise exerts profound protective effects on the cardiovascular system, even in the setting of a poor diet. Learn more about the benefits of aerobic exercise in our overview article.

  • Urinary excretion of isothiocyanates – bioactive compounds derived from cruciferous vegetables – is associated with a lower risk of breast cancer, a 2003 study found. Women with the highest levels of isothiocyanates in their urine were half as likely to have breast cancer, compared to women with the lowest levels.

    Researchers measured isothiocyanates in the urine of 674 women, half of whom had breast cancer. They also collected information about the women’s demographics, lifestyles, reproductive histories, and dietary intake of cruciferous vegetables.

    They found high urinary isothiocyanate levels reduced the women’s risk of having breast cancer by half, even after considering age, menopausal status, and other factors that influence breast cancer risk. This protective association was true in pre- and postmenopausal women.

    Isothiocyanates are bioactive compounds derived from glucosinolates, a large class of precursor molecules found in cruciferous vegetables. Robust evidence demonstrates that isothiocyanates switch on the activity of cellular protective mechanisms that reduce the risk of many chronic diseases, including cancer.

    Assessing isothiocyanate exposure via dietary reports of glucosinolate intake is often inaccurate due to reporting biases as well as differences in plant glucosinolate content, which varies across species and cultivars. In addition, inter-individual differences in how people metabolize isothiocyanates and their precursors may influence exposure. Measuring urinary isothiocyanate metabolites likely provides more accurate measures of habitual intake and metabolite-specific exposures that positively influence risk.

    Sulforaphane is an isothiocyanate with potent antioxidant, anti-inflammatory, and anticancer properties. Learn more about sulforaphane’s effects on cancer in this clip featuring Dr. Jed Fahey.

  • From the publication:

    Some foods and supplements influence testosterone levels in various animals. The two main mechanisms are the direct increase in testosterone levels or suppression of the decrease in testosterone production due to testicular toxicity. Foods or supplements raise testosterone production in three ways: 1) regulating LH [ luteinizing hormone], the hormone that stimulates the production of testosterone, 2) regulating testosterone synthase in the testis, and 3) regulating testosterone-degrading enzymes. In contrast, suppression of the decrease in testosterone depends on the antioxidant effect of the foods and supplements.

    […]

    LH is a gonadotropin that is released by the pituitary glands. Garlic, l-carnitine, selenium, vitamin C, CoQ10, qleuropein, and resveratrol regulate the LH [ luteinizing hormone] secretion. Secreted LH acts on testis receptors and is involved in the synthesis of testosterone from cholesterol. Lactic acid bacteria enhance testosterone production by increasing Leydig cells in the testis. Linoleic acid, maca, and piperin raise testosterone levels by increasing the levels of enzymes involved in testosterone synthesis. These two pathways of testosterone production would be a promising target for treatment. Foods or supplements that have been shown to increase testosterone might act on these pathways. In contrast, testosterone is metabolized to estradiol by aromatase. Chrysin increased testosterone levels by inhibiting aromatase activity. Although detailed mechanistic studies and clinical trials are required to validate the findings, the effects of these foods on testosterone provide potential therapeutic options.

  • The gut microbiome influences the development of social skills later in life, a recent study in fish has found. Fish that have delayed microbiome development show distinct differences in their brain structure and behavior compared to those with appropriately timed development.

    Researchers studied zebrafish, which are naturally social, to see how the microbiome affected the animals' behavior. Using a special type of zebrafish that lacked a microbiome, they inoculated one group of fish with bacteria immediately after birth to promote microbiome development. They delayed the inoculation of another group of fish by one week.

    They found that the fish that had delayed microbiome development exhibited more neural circuits in their brains and fewer microglia – a type of immune cell that “prunes” the brain and is necessary for normal development. These fish were also less social than the fish that had appropriately timed microbiome development.

    This study suggests that the microbiome influences the social behavior of zebrafish by reducing microglial pruning. Although the study was conducted using fish, other research suggests that these findings could translate to mammals, including humans. Learn more about the role of the gut microbiome in this episode featuring Dr. Eran Elinav.

  • Men who eat a pro-inflammatory diet – rich in sugar, refined carbohydrates, and fats – are 30 percent more likely to have low testosterone levels, a 2021 study found. Having obesity nearly doubles this risk.

    Researchers analyzed dietary records of more than 4,000 men living in the United States and assigned each diet a score that reflected the inflammatory nature of the foods the men ate. In general, highly refined foods such as snacks, sugary drinks, processed meat, and fried foods are pro-inflammatory, but fresh fruits, vegetables, nuts, legumes, and fish are anti-inflammatory. They also assessed the men’s sex hormone status.

    They found that men whose diet scores indicated that they ate a pro-inflammatory diet had lower testosterone levels than those who ate an anti-inflammatory diet. Men with the highest pro-inflammatory diet scores were nearly 30 percent more likely to have low testosterone levels. After considering other factors that influence testosterone levels, such as age, race, caloric intake, smoking status, education level, and body mass index, men who had obesity and had the highest pro-inflammatory diet scores were nearly 60 percent more likely to have low testosterone levels.

    Testosterone is a male sex hormone that plays important roles in reproduction and sexual function. As many as one-half of all men living in the United States have low testosterone levels, which can cause low libido, lack of energy, and low mood. Research has shown that low testosterone levels are associated with higher levels of pro-inflammatory cytokines in the body.

    The findings from this study suggest that a pro-inflammatory diet promotes low testosterone levels in men, especially those who have obesity. Other studies suggest the risk of low testosterone quadruples in the setting of obesity and a pro-inflammatory diet. Choosing foods that reduce inflammation may be beneficial in restoring testosterone levels. Check out this smoothie recipe, which is rich in anti-inflammatory fruits and vegetables.

    Read study abstract.

  • From the publication:

    In conclusion, collectively, the main stream of this specific research approach reveals that oral administration of honey enhances serum testosterone level in males. The mechanisms by which honey increases serum testosterone may be by enhancing the production of luteinizing hormone, enhancing the viability of Leydig cells, reducing testicular oxidative injury, enhancing StAR gene expression, and inhibiting aromatase activity in the testes (Fig. 1). In addition, honey has been found to contain various bioactive compounds (e.g., phenolic acids) that may improve testosterone production. However, still, there is lack in the number of human studies in this research context. Therefore, conducting clinical trials that reveal the mechanisms of honey on serum testosterone level will be of great importance.

  • From the publication:

    Many factors, including external, environmental and internal factors, influence testosterone levels. The impact of energy intake derived from a testosterone-boosting diet depends on a human body mass. In the case of people of healthy body mass, insufficient energy intake may result in a reduction in testosterone levels in men. The same energy deficit in obese people, may, in turn, result in a neutral or positive impact on the levels of the hormone. Undoubtedly, nutritional deficiency, and particularly of such nutrients as zinc, magnesium, vitamin D, together with low polyphenols intake, affects the HPG [hypothalamic–pituitary–gonadal] axis. The levels of mental and oxidative stress can also adversely impact the axis. The higher the cortisol levels in a human body, or the higher its daily fluctuation, the lower the testosterone levels. What is more, the effect seems to be strengthened by excessive body weight, which is related to the increased oxidative stress affecting the functions of the Leydig cells. Other factors which might disrupt testosterone synthesis may be the length and quality of sleep. Even though the issue is relatively unknown, it appears that both sleep deprivation (shorter than five hours) and low quality of sleep (sleeping with the light on, sleeping during the day, under the influence of alcohol) impact the testosterone levels negatively.

  • From the publication:

    Patient interest in fertility and testicular size preservation and a desire to avoid lifelong medical therapy with testosterone drives the need to identify non-TTh [non-testosterone therapy] for hypogonadism. Medical therapies that can stimulate endogenous testosterone production include hCG [human chorionic gonadotropin], AIs [aromatase inhibitors], and SERMs [selective estrogen receptor modulators], all of which demonstrate efficacy in increasing serum testosterone levels and good safety profiles. Natural therapies to increase testosterone production include diet and exercise, weight loss, improved sleep, decreasing stress, and varicocele repair. Diet, exercise, and weight loss provide a means to potentially reverse comorbidities that are closely linked to hypogonadism. Improvements in sleep quality and duration and decreasing stress are additional lifestyle modifications that can improve testosterone levels without the need for lifelong medication. Varicocele repair also can increase testosterone levels, although rigorous data supporting its use remain lacking. Patients considering TTh should be counseled on disease modification and the possibility of discontinuing TTh in the future, before initiation of therapy, and the alternatives discussed in this review also should be considered first in appropriate candidates.

    […]

    Diet, exercise, and weight loss

    – 12-wk lifestyle modification program involving aerobic exercise and diet modification significantly increased mean testosterone levels

    – 52-wk program of diet and exercise significantly increased mean serum testosterone levels

    – Individuals who lost 10% of weight between visits showed a significant increase in testosterone levels

    – Weight loss through low-calorie diets or bariatric surgery was associated with significant increases in total testosterone levels

    Improvements in sleep

    – Men with OSA treated with UPPP had significant 3-mo postoperative increases in testosterone levels

    – Restriction of sleep to 5 h/night decreased testosterone levels by 10-15%

    Stress reduction

    – Men with high stress levels had significantly lower serum testosterone levels compared with controls

    – Men with higher work stress had higher than expected incidence of hypogonadism

    Varicocele repair

    – Varicocelectomy significantly increased mean testosterone levels

    – Varicocele repair significantly increased testosterone levels

    – Significantly increased total testosterone levels were found at 12-mo follow-up after varicocelectomy

    – Mean serum total testosterone significantly increased after varicocelectomy

  • From the article:

    For the first 10 weeks, all participants were placed on a strict 600 kcal per day very-low calorie diet. They were also encouraged to abstain from alcohol and perform at least 30 minutes a day of moderate exercise. From the 11th through the 56th week, participants in both groups used a weight-maintenance diet based on the Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) Total Wellbeing Diet comprising of normal foods.

    Every 10 weeks over the 56-week-long study, 49 men also received injections of 1,000mg of intramuscular testosterone undecanoate, and 51 took placebo.

    At the end of 56 weeks, both groups lost roughly 11 kg (24.2 lb). But those in the testosterone group lost almost exclusively fat, while those on placebo lost both lean and fat. The men taking testosterone lost 3 kg (6.6 lb) more body fat than those on placebo and maintained their muscle mass, while those on placebo lost 3.5 kg (7.7 lb) of muscle mass.

    View full publication

  • The fasting-mimicking diet – a short-term, low-protein, low-carbohydrate diet – improves metabolism and increases immune cell populations that target cancer, according to a 2021 study. Participants who followed the five-day dietary protocol found it easy to adhere to and experienced few ill effects other than fatigue.

    The study involved 101 cancer patients who followed a fasting-mimicking diet that provided up to 600 calories on the first day and up to 300 calories on the remaining days. They repeated the dietary protocol every three to four weeks – up to eight times in all. The patients followed their normal diets between the fasting-mimicking periods but were encouraged to adhere to healthy lifestyles.

    The study’s investigators found that the fasting-mimicking diet reduced the patients' glucose by 18 percent, insulin by 50 percent, and IGF-1 (a growth factor involved in cancer development) by 30 percent. These changes remained stable over the duration of the study. They also found that levels of immunosuppressive cells decreased, but CD8+ T cells – the primary drivers of anti-tumor immunity – increased.

    Research shows that the fasting-mimicking diet creates a hostile microenvironment for cancer cells, sensitizing them to chemotherapy drugs and promoting cell death while preserving healthy cells. This sensitization exploits cancer cells' inability to adapt to extreme environments – a critical aspect of treating certain types of aggressive cancers and preventing their recurrence.

    These findings suggest that the fasting-mimicking diet is a safe and useful adjunct to chemotherapy. Learn about other benefits of the fasting-mimicking diet in this video featuring its creator, Dr. Valter Longo.

  • Maintaining a healthy body weight presents challenges for many people. Previous research has shown that the timing of food intake plays important roles in managing body weight. Findings from a recent study suggest that late-night eating is counter to the body’s circadian rhythms, increasing the risk of weight gain.

    Circadian rhythms modulate a wide array of the body’s physiological processes, including the production of hormones that regulate sleep, hunger, metabolism, and others, ultimately influencing body weight, performance, and susceptibility to disease. Coordination of meal timing with the circadian rhythm can affect aspects of metabolic health, including glucose regulation and insulin sensitivity.

    The study involved 16 adults (average age, 37 years) who had overweight or obesity. The participants followed an “early” eating schedule and then a “late” eating schedule for six days each, separated by a wash-out period of three to 12 weeks. The researchers controlled the participants' caloric intake, physical activity, sleep, and light exposure throughout the two interventions. They also collected adipose tissue samples from the participants for analysis of gene expression. Participants reported their hunger and appetite.

    The researchers found that when the participants ate later in the day, their hunger and appetite-regulating hormones increased, but their energy expenditure decreased. In addition, eating late altered biochemical pathways involved in fat metabolism and storage.

    These findings suggest that eating late influences appetite, energy expenditure, and molecular pathways in fat tissue, underscoring the role of circadian rhythmicity in bodyweight management. Watch this episode in which Dr. Satchin Panda summarizes tips and strategies that anyone can follow to ensure a healthy circadian pattern.

  • Although epidemiological and observational data support the role of nutrition in maintaining cognitive health in aging, establishing which components of a diet support brain health is difficult and error-prone when relying on food intake surveys and biomarker studies. A recent metabolomics study identified specific dietary components associated with either preventing or promoting cognitive decline.

    Metabolomics is an emerging field of study that involves the measurement of all metabolites – the intermediate or end products of metabolism – in a biological specimen. Many metabolites are produced when food is digested and further metabolized by gut microbes.

    The investigators analyzed food-related and microbiota-derived metabolites in the blood of more than 800 adults living in two distinct regions of France. The participants completed a battery of neuropsychological tests and provided information about their overall health.

    The investigators found that plant-based food metabolites (from cocoa, coffee, mushrooms, and red wine) and microbiota-derived metabolites (from microbial metabolism of polyphenol-rich apples, cocoa, green tea, blueberries, oranges, and pomegranates) appeared to exert a protective effect against cognitive decline. Conversely, metabolites derived from caffeine, alcohol, and artificial sweeteners appeared to promote cognitive decline.

    These findings suggest that specific plant-based dietary components protect against cognitive decline and support the rationale for a plant-rich diet. Some evidence suggests that a ketogenic diet promotes cognitive function and protects the brain against cognitive decline. Learn how to incorporate fiber-rich plant-based foods into a ketogenic diet in this clip featuring Dr. Dominic D'Agostino.

  • The DASH Diet slows epigenetic aging.

    The DASH Diet (Dietary Approaches to Stop Hypertension) is a dietary pattern that emphasizes heart-healthy eating. Widely recognized for its evidence-based guidelines, DASH is rich in fruits, vegetables, fish, poultry, legumes, and healthy fats and is low in saturated fats and sweets. Findings from a 2021 study suggest that the DASH diet slows epigenetic aging.

    Epigenetic age acceleration is a phenomenon that occurs when an individual’s epigenetic (biological) age exceeds their chronological age. Early research relied on measures of either intrinsic or extrinsic factors to measure age acceleration. Newer methods rely on clinical and functional biomarkers, which have stronger predictive abilities for the time to chronic diseases and death.

    The study utilized data from nearly 2,000 adults (average age, 67 years) who were enrolled in the Framingham Heart Study Offspring Cohort. Investigators collected information about the participants' usual dietary intake and assigned a score based on the overall quality and adherence to DASH guidelines. They also collected blood samples from the participants for analysis and determination of their DNA methylation status using three epigenetic age acceleration measures: Dunedin Pace of Aging Methylation, GrimAge acceleration, and PhenoAge acceleration.

    They found that all three age acceleration measures indicated that having a higher DASH score was associated with slowed epigenetic aging, even after taking age, sex, smoking status, body mass index, physical activity, alcohol consumption, and caloric intake into consideration. This slow aging translated to roughly one additional year of life. Higher intakes of vegetables, fruits, nuts, legumes, and whole grains were associated with slower aging, while higher intakes of red and processed meat and sodium were associated with faster aging.

    These findings suggest that the DASH dietary pattern slow epigenetic aging and underscores the importance of implementing lifestyle modifications to promote health and longevity. Learn more about epigenetic age acceleration in these clips featuring epigenetics experts Dr. Steve Horvath and Dr. Morgan Levine.

  • Fast food during pregnancy harms both mother and offspring and interferes with milk production.

    Fast foods – burgers, fries, pizzas, sugar-sweetened drinks, and many others – are often high in calories, saturated fat, added sugars, and salt. Regular consumption of fast foods is associated with an increased risk for many chronic diseases. Findings from a recent study suggest that eating fast food during pregnancy negatively influences maternal health during pregnancy and undermines the nutritional quality of a mother’s breast milk.

    Breast milk is a complex and highly dynamic fluid that changes in composition in response to the growing infant’s needs. It contains both nutritional and non-nutritional components and is profoundly influenced by maternal health and dietary intake.

    The investigators fed one group of mice a high-fat, high-sugar diet that mimicked the nutritional content of fast food before, during, and after pregnancy. They fed another group a normal diet. They assessed the mothers' metabolic health, milk output, and milk composition, and assessed the offspring’s health.

    They found that the mice that ate the high-fat, high-sugar diet were heavier and had higher blood glucose and insulin levels during pregnancy than the mice that ate the normal diet. They also had fatty livers and showed signs of changes in their pancreatic tissues. More of the offspring born to the mice that ate the high-fat, high-sugar diet died during the lactation period due to poor maternal mammary gland development and diminished milk protein production.

    These findings suggest that eating foods that are high in fat and sugar (such as fast foods) during pregnancy negatively influences maternal health and undermines the nutritional quality of a mother’s breast milk. Learn more about breast milk and breastfeeding in our overview article.

  • From the article:

    The researchers placed mice prone to developing AAA on a calorie-restricted diet for 12 weeks and found that the animals were less likely to develop aneurysms than control mice fed a normal diet. The calorie-restricted mice also showed lower rates of AAA rupture and death.

    The researchers determined that calorie restriction reduced the levels of an enzyme called MMP2 that degrades the protein matrix surrounding blood vessels. This was because, after 12 weeks of reduced calorie intake, vascular smooth muscle cells in the wall of the aorta up-regulated a metabolic sensor protein called SIRT1, which can epigenetically suppress multiple genes, including MMP2. The researchers found that calorie restriction was unable to reduce MMP2 expression and the incidence of AAA in mice whose vascular smooth muscle cells lack SIRT1.

    View full publication

  • Flavonoid-rich cocoa supplement reverses arterial stiffness and decreases blood pressure.

    Arterial stiffness, a condition in which the walls of arteries become more rigid, increases with age and is a strong risk factor for hypertension. The links between arterial stiffness and hypertension are likely bidirectional, with aortic stiffening driving increases in systolic pressure, and elevated pressures promoting vascular damage and accelerated stiffening. Findings from a new study suggest that flavonoid compounds in cocoa reverse arterial stiffness.

    Cocoa, the principal component of chocolate, is derived from the cacao tree. A wide range of beneficial health effects have been attributed to consumption of cocoa and chocolate, especially dark chocolate, which is rich in flavonoids. Cocoa and chocolate have the highest concentrations of flavonoids among commonly consumed foods, with roughly 10 percent of the weight of cocoa powder coming from flavonoids. Robust evidence suggests that cocoa flavonoids improve blood flow, lower blood pressure, promote healthy blood lipid concentrations, lower the risk of cardiovascular disease, protect the skin against the sun, and improve blood flow to the brain.

    The investigators conducted a series of single-person trials in 11 healthy adults. Participants consumed six cocoa flavonoid capsules (providing 862 milligrams of cocoa flavonoids) every morning on alternating days for eight consecutive days. On days when they didn’t take the cocoa flavonoid capsules, they took a placebo. Participants wore devices that measured their blood pressure, heart rate, and pulse wave velocity (a measure of arterial stiffness) before and every 30 minutes for the first three hours after taking the capsules and then every hour afterward for a total of 12 hours per day.

    The investigators found that when the participants took the cocoa supplement, the participants' blood pressure dropped by as much as 1.7 mmHg and their pulse wave velocity decreased by as much as 0.14 m/s. These effects were observed only if the participant had high blood pressure. The greatest effects occurred in the first three hours after taking the cocoa, with the blood pressure dropping approximately 5 mmHg. Blood pressures dropped again at approximately eight hours after consuming the cocoa supplement, likely due to bacterial metabolism of the flavonoids in the gut.

    These findings suggest that a flavonoid-rich cocoa supplement reduces blood pressure and markers of arterial stiffness in people with high blood pressure. Larger studies are needed to confirm these findings.

  • Resistant starch reduces the risk of certain hereditary cancers by roughly half.

    Lynch syndrome increases a person’s risk of having several types of cancer, particularly colorectal cancer. It is an inherited condition, affecting one out of 279 people worldwide and accounting for 2 to 4 percent of all colorectal cancer cases and 2.5 percent of endometrial cancer cases. Findings from a recent study suggest that supplemental resistant starch reduces the risk of cancer among people with Lynch syndrome.

    Resistant starch is a type of carbohydrate that resists digestion in the small intestine. Instead, resistant starch undergoes microbial fermentation in the colon, providing nutrients for the microbes, and producing butyrate, a short-chain fatty acid that supports the health of colonocytes – the cells that line the colon and rectum (the end portion of the colon). Foods that contain resistant starch include breads, pasta, legumes, nuts, seeds, bananas, and starchy vegetables, such as potatoes. A 3-ounce portion of baked potatoes typically provides 3.6 grams of resistant starch. Evidence suggests that resistant starch consumption alters microRNA expression, potentially moderating the cancer risks associated with red meat consumption.

    The study was part of the CAPP2 trial, an ongoing investigation to identify strategies that reduce the risk of certain hereditary cancers. The study involved nearly 1,000 adults (average age at recruitment, 45 years) who had Lynch syndrome. Half of the participants took 30 grams of resistant starch daily for an average of two years, while the other half took a placebo. The investigators tracked the participants for up to 20 years to see if they developed Lynch syndrome-related cancers.

    They found that resistant starch did not reduce the incidence of colorectal cancers, but it did reduce the incidence of other Lynch syndrome-related cancers (especially those of the upper digestive tract) by roughly half. The protective effect of resistant starch on cancer incidence endured for approximately 10 years after discontinuation of the supplement.

    These findings suggest that resistant starch protects against certain forms of hereditary cancers and underscores the role of diet in preventing cancer. For example, some evidence suggests that ketones exert anti-tumor effects. Learn more in this clip featuring Dr. Dominic D'Agostino.

  • Branched chain amino acids ameliorate cognitive losses associated with brain injury.

    Approximately 1.5 million people living in the United States experience a traumatic brain injury (TBI) – a disruption in normal brain function caused by an external mechanical force – each year. TBI causes both acute and chronic effects, including cognitive dysfunction. Findings from a 2009 study suggest that a branched chain amino acid-rich supplement ameliorates TBI-associated cognitive dysfunction.

    The branched chain amino acids, which include leucine, isoleucine, and valine, play important roles in muscle protein synthesis. However, they also influence brain health because they contribute nitrogen molecules essential for neurotransmitter synthesis (particularly glutamate and gaba) and modulate brain neurochemistry.

    The investigators measured branched chain amino acid concentrations in the brains of mice that had experienced a brain injury. Then they provided branched chain amino acids in the drinking water of brain-injured and non-injured mice for five days, commencing on the second day post-injury. Finally, they subjected both groups of mice to cognitive performance tests.

    They found that brain concentrations of branched chain amino acids were markedly lower in the brain-injured mice, resulting in decreased function in the hippocampus, an area of the brain involved in learning. However, brain-injured mice that received the amino acids exhibited higher amino acid concentrations in their brains and better performance on cognitive tests.

    These findings suggest that branched chain amino acids restore aspects of brain neurochemistry and ameliorate cognitive losses after TBI. Some bioactive compounds in plants may be beneficial in managing the symptoms of TBI, including sulforaphane, a compound derived from broccoli, which increases brain glutathione concentrations. Learn more in this clip featuring Dr. Rhonda Patrick.

  • Dietary fiber improves symptoms of metabolic syndrome.

    Metabolic syndrome is a constellation of medical conditions that includes high blood pressure, high blood glucose, unhealthy cholesterol levels, and excess abdominal fat. Having metabolic syndrome increases a person’s risk of heart disease, stroke, and diabetes. A 2009 study found that supplemental psyllium and guar gum improved symptoms associated with metabolic syndrome.

    Psyllium, found in husks of the psyllium (Plantago ovata) seed, and guar gum, found in guar beans and commonly used as a food additive, are types of soluble dietary fiber. Soluble fibers dissolve in water and pass intact into the large intestine, where they are converted by colonic bacteria to prebiotic gels. Evidence indicates that consumption of soluble dietary fibers is associated with improved metabolic function, cardiovascular health, and gut function.

    The six-month study involved 141 adults (average age, ~58 years) who had metabolic syndrome. The investigators randomly assigned participants to one of three groups. One group consumed supplemental psyllium husk powder twice a day before meals, while the other consumed guar gum. The third group consumed a standard diet. Investigators measured the participants' metabolic markers, blood lipids, blood pressure, and body weight before and after the intervention.

    Participants who consumed the psyllium and guar gum exhibited reduced blood glucose, insulin, low-density lipoprotein cholesterol, and apolipoprotein B (a component of very-low-density lipoprotein), compared to their baseline levels. Those who took the psyllium showed marked improvements in their triglycerides (~13 percent lower) and blood pressures (systolic, ~4 percent lower; diastolic, ~3 percent lower). Those who took the guar gum lost slightly more weight than those who took the psyllium. Participants who followed the standard diet did not exhibit significant improvements in any measures.

    These findings suggest that soluble dietary fibers such as psyllium and guar gum reduce weight and improve markers of metabolic health in people with metabolic syndrome. Dietary fibers also maintain gut barrier function, which is often impaired in metabolic syndrome due to increased intestinal permeability. Learn more about intestinal permeability in our overview article.

  • Anthocyanins reduce cholesterol and triglyceride levels.

    Anthocyanins are blue- and purple-colored polyphenolic compounds found in fruits and vegetables, including blueberries, raspberries, eggplants, and others. Robust evidence indicates that anthocyanins exert antioxidant, anti-inflammatory, and/or neuroprotective effects and may reduce a person’s risk of developing cardiovascular disease, cancer, and type 2 diabetes. Findings from a recent meta-analysis found that anthocyanins reduce cholesterol and triglyceride levels in people with dyslipidemia.

    Dyslipidemia is an abnormal condition in which levels of blood lipids, such as cholesterol or triglycerides, are too high or too low. Dyslipidemia can be caused by genetic or lifestyle factors and may increase a person’s risk of developing atherosclerosis, a condition characterized by high levels of triglycerides and small, dense low-density lipoprotein (LDL) particles, and low levels of high-density lipoprotein (HDL) cholesterol.

    The investigators conducted a meta-analysis, a type of study that analyzes the data derived from multiple studies using objective, statistical formulas to identify a common effect. Their analysis only included randomized, placebo-controlled trials in adults that examined links between anthocyanin supplementation and total cholesterol, triglyceride, LDL, and HDL levels (measured in milligrams per deciliter [mg/dL]). Six studies, involving nearly 600 participants, met their criteria.

    They found that anthocyanin supplementation had favorable effects on total cholesterol (24.06 mg/dL decrease), triglycerides (26.14 mg/dL decrease), LDL (22.10 mg/dL decrease) and HDL (5.58 mg/dL increase). These effects were observed even when considering the participants' age, body mass index, anthocyanin dose, duration of intervention, and ethnicity.

    These findings suggest that anthocyanins, a class of polyphenols, markedly improve blood lipid concentrations. They also underscore the value of dietary measures in managing dyslipidemia. Learn more about polyphenols in our overview article.

  • Very low-calorie diets elicit extensive changes to the gut microbiota, influencing weight loss.

    Many popular diet programs emphasize calorie reduction as a means to lose weight. However, this approach to weight loss minimizes evidence suggesting that the gut microbiota plays important roles in body weight and likely influences the host’s metabolic response to diet. Findings from a recent study suggest that very low-calorie diets elicit extensive changes to the gut microbiota, influencing how much weight a person loses when dieting.

    Low-calorie diets (1,200 to 1,500 calories per day) and very low-calorie diets (less than 800 calories per day) have gained popularity in recent decades. These diets often rely on the use of meal replacements, typically in the form of ready-made meals, shakes, or bars. When combined with behavior modification, evidence suggests that low-calorie and very low-calorie diets are useful strategies for losing weight.

    The investigators drew on data from the PREVIEW study, a three-year lifestyle intervention study aimed at type-2 diabetes prevention. The current study involved more than 2,200 adults (aged 20 to 70 years) with overweight or obesity and pre-diabetes. Participants consumed a meal replacement that provided approximately 810 calories and 13 grams of fiber daily for eight weeks. They were also allowed to consume up to 400 grams (about 200 calories) of non-starchy vegetables daily. Before and after the intervention, participants provided fecal samples for microbial sequencing.

    The investigators observed that the overall makeup of the participants' gut microbial populations underwent considerable changes over the eight-week intervention. Not only did microbial numbers (termed “richness”) increase, but the diversity of microbes increased, as well. In addition, the numbers of bacteria that may be beneficial for metabolic health, such as Akkermansia and _ Christensenellaceae_, increased, but butyrate production decreased, an indication of fewer butyrate-producing microbes. Butyrate plays important roles in maintaining gut health. These changes were correlated with changes in body fat and weight.

    These findings suggest that very low-calorie diets induce marked changes in the overall composition of microbes in the gut, influencing changes in body fat and weight. Other issues complicate weight loss, however. For example, excess body weight has profound, deleterious effects on the gut microbiome, driving dysbiosis and impairing critical aspects of nutrient metabolism. Of particular concern is the inability to metabolize flavonoids, some of which participate in fat metabolism. This dysbiosis persists, even after weight loss, likely promoting recurrent (or “yo-yo”) obesity. Learn more about this phenomenon in this clip featuring Dr. Eran Elinav.

  • This is a Jeff Volek study and used hard biomarkers, checking ketones daily.

    From the article:

    In the study, which appears in the journal Military Medicine, participants on the keto diet lost an average of almost 17 pounds and were able, with support of counselors, to maintain ketosis for 12 weeks. As a group, they lost more than 5 percent of their body fat, almost 44 percent of their belly, or visceral, fat and had a 48 percent improvement in insulin sensitivity – a marker that predicts risk of diabetes.

    […]

    The ketogenic diets in the study included no caloric restrictions, just guidance about what to eat and what to avoid. Carbs were restricted to about 30 to 50 grams daily, with an emphasis on nuts and non-starchy vegetables.

    […]

    Keto diet participants had near-daily check-ins during which they reported blood ketone measurements from a self-administered finger-prick test and received feedback, usually through text messages, from the research team. Ketosis was defined as a blood concentration of ketones, chemicals made in the liver, between 0.5 and 5.0 mM (millimolar).

  • From the article:

    According to a new study by researchers at Wake Forest Baptist Medical Center, the way to zero in and reduce visceral fat is simple: eat more soluble fiber from vegetables, fruit and beans, and engage in moderate activity.

    The study found that for every 10-gram increase in soluble fiber eaten per day, visceral fat was reduced by 3.7 percent over five years. In addition, increased moderate activity resulted in a 7.4 percent decrease in the rate of visceral fat accumulation over the same time period.

    […]

    Researchers found that increased soluble fiber intake was associated with a decreased rate of accumulated visceral fat, but not subcutaneous fat.

    “There is mounting evidence that eating more soluble fiber and increasing exercise reduces visceral or belly fat, although we still don’t know how it works,” Hairston said. “Although the fiber-obesity relationship has been extensively studied, the relationship between fiber and specific fat deposits has not. Our study is valuable because it provides specific information on how dietary fiber, especially soluble fiber, may affect weight accumulation through abdominal fat deposits.”

  • Inadequate sleep drives abdominal fat gains.

    Visceral fat is body fat that is stored in the abdominal cavity near the liver, pancreas, and intestines. The accumulation of visceral fat is linked to type 2 diabetes, insulin resistance, inflammatory diseases, certain types of cancer, cardiovascular disease, and other obesity-related conditions. Findings from a recent study suggest that not getting enough sleep increases the risk of developing excess visceral fat.

    Sleep is essential for human health. Not getting enough sleep or having poor, fragmented sleep promotes the development of many chronic illnesses, including cardiovascular disease, hypertension, diabetes, stroke, obesity, and depression. Scientists don’t fully understand the mechanisms that drive these effects, but some evidence suggests that disturbances in circadian rhythms play vital roles.

    The trial involved 12 healthy young adults (aged 19 to 39 years) who engaged in an in-patient sleep study. Participants were allowed to have either a full night of sleep (nine hours of sleep opportunity) or restricted sleep (four hours of sleep opportunity) for two weeks. After a three-month washout period, participants repeated the study with the opposite sleep experience. The investigators measured the participants’ caloric intake, energy expenditure, body weight, body composition, and fat distribution throughout the study period.

    They found that when participants were sleep-restricted, they consumed approximately 13 percent more protein and 17 percent more fat (translating to about 300 calories) daily, but their overall energy expenditure did not change. Sleep-restricted participants also gained weight. Much of this weight was in the abdominal area, with a 9 percent increase in total abdominal fat area and an 11 percent increase in visceral fat, compared to when they got a full night’s sleep.

    These findings suggest that insufficient sleep increases caloric intake and promotes weight gain and visceral fat increases. Learn more about the harmful health effects of insufficient sleep in this episode featuring sleep expert Dr. Matt Walker.

  • A low-glycemic index Mediterranean diet and aerobic exercise corrects gut microbial imbalance in people with fatty liver disease.

    Non-alcoholic fatty liver disease, or NAFLD, is a syndrome that encompasses multiple states of liver dysfunction, including steatosis (fatty liver), nonalcoholic steatohepatitis, and cirrhosis. It is the most common liver chronic liver condition among people living in the United States, affecting roughly 90 percent of people with obesity, or about 25 percent of the overall population. A dominant feature of NAFLD is dysbiosis, an imbalance in the types and numbers of microbes in the gut. Findings from a recent study suggest that eating a low-glycemic index Mediterranean diet and engaging in aerobic exercise restores gut microbial balance in people with NAFLD.

    Glycemic index refers to a value (between 0 and 100) assigned to a defined amount of a carbohydrate-containing food based on how much the food increases a person’s blood glucose level within two hours of eating, compared to eating an equivalent amount of pure glucose, which has a value of 100. Whereas eating high glycemic index foods induces a sharp increase in blood glucose levels that declines rapidly, eating low glycemic index foods generally results in a lower blood glucose concentration that declines gradually.

    The Mediterranean dietary pattern is rich in foods that have a low glycemic index, including fruits, vegetables, olive oil, legumes, fish, and poultry. Previous research demonstrated that a Mediterranean diet in conjunction with aerobic exercise improves measures of NAFLD but did not identify the mechanism that drove these improvements.

    The current study involved 109 adults (average age, 53 years) who had been diagnosed with NAFLD. The investigators randomly assigned the participants to receive one of six interventions: low glycemic index Mediterranean diet; aerobic exercise program (with or without the low glycemic index Mediterranean diet); combined aerobic exercise and resistance training program (with or without the low glycemic index Mediterranean diet); or no intervention. The investigators collected stool samples from the participants and sequenced the microbial populations in the samples.

    They found that compared with other dietary/exercise interventions, a low-glycemic index Mediterranean diet in conjunction with aerobic exercise exerted robust effects on the participants' gut microbial population. These effects corrected the participants' dysbiosis and promoted increases in populations of microbes that benefit gut health, including Akkermansia, Firmicutes, and Ruminococcaceae.

    These findings suggest that dietary measures in conjunction with exercise have favorable effects on the gut microbiota of people with NAFLD, providing insights into the mechanisms that drive improvements in disease status. Evidence from cell culture studies suggests that berberine, a bioactive dietary compound, provides protection against NAFLD. Read our overview article to learn more about berberine.

  • From the article:

    Gomez-Pinilla and study co-author Rahul Agrawal, a UCLA visiting postdoctoral fellow from India, studied two groups of rats that each consumed a fructose solution as drinking water for six weeks. The second group also received omega-3 fatty acids in the form of flaxseed oil and docosahexaenoic acid (DHA), which protects against damage to the synapses – the chemical connections between brain cells that enable memory and learning.

    […]

    The animals were fed standard rat chow and trained on a maze twice daily for five days before starting the experimental diet. The UCLA team tested how well the rats were able to navigate the maze, which contained numerous holes but only one exit. The scientists placed visual landmarks in the maze to help the rats learn and remember the way.

    Six weeks later, the researchers tested the rats' ability to recall the route and escape the maze. What they saw surprised them.

    “The second group of rats navigated the maze much faster than the rats that did not receive omega-3 fatty acids,” Gomez-Pinilla said. “The DHA-deprived animals were slower, and their brains showed a decline in synaptic activity. Their brain cells had trouble signaling each other, disrupting the rats' ability to think clearly and recall the route they’d learned six weeks earlier.”

    The DHA-deprived rats also developed signs of resistance to insulin, a hormone that controls blood sugar and regulates synaptic function in the brain.

  • Dietary interventions can change metabolite levels in the tumour microenvironment, which might then affect cancer cell metabolism to alter tumour growth. Although caloric restriction (CR) and a ketogenic diet (KD) are often thought to limit tumour progression by lowering blood glucose and insulin levels, we found that only CR inhibits the growth of select tumour allografts in mice, suggesting that other mechanisms contribute to tumour growth inhibition. A change in nutrient availability observed with CR, but not with KD, is lower lipid levels in the plasma and tumours. Upregulation of stearoyl-CoA desaturase (SCD), which synthesises monounsaturated fatty acids, is required for cancer cells to proliferate in a lipid-depleted environment, and CR also impairs tumour SCD activity to cause an imbalance between unsaturated and saturated fatty acids to slow tumour growth. Enforcing cancer cell SCD expression or raising circulating lipid levels through a higher-fat CR diet confers resistance to the effects of CR. By contrast, although KD also impairs tumour SCD activity, KD-driven increases in lipid availability maintain the unsaturated to saturated fatty acid ratios in tumours, and changing the KD fat composition to increase tumour saturated fatty acid levels cooperates with decreased tumour SCD activity to slow tumour growth. These data suggest that diet-induced mismatches between tumour fatty acid desaturation activity and the availability of specific fatty acid species determine whether low glycaemic diets impair tumour growth.

  • Resistant starch reduces colorectal cancer risks associated with a high-red meat diet.

    Colorectal cancer is the third most common cancer worldwide. Robust evidence suggests that red meat consumption markedly increases a person’s risk of developing colorectal cancer.. Findings from a 2014 study suggest that resistant starch consumption alters microRNA expression, potentially moderating the cancer risks associated with red meat consumption.

    Resistant starch is a type of carbohydrate that resists digestion in the small intestine. Instead, resistant starch undergoes microbial fermentation in the colon, providing nutrients for the microbes and producing butyrate, a short-chain fatty acid that supports the health of colonocytes – the cells that line the colon and rectum (the end portion of the colon). Foods that contain resistant starch include breads, pasta, legumes, nuts, seeds, bananas, and starchy vegetables, such as potatoes. Cooking and preparation techniques alter resistant starch content in foods, however. For example, a study found that a 3-ounce portion of baked potatoes typically provides 3.6 grams of resistant starch, but a similar portion of boiled potatoes provides just 2.4 grams.

    MicroRNAs are single-stranded RNA molecules that play roles in the regulation of gene expression. They calibrate as much as 30 percent of mammalian protein-encoding genes. MicroRNA expression is typically dysregulated in the setting of cancer. However, evidence from an in vitro study suggests that butyrate modulates microRNA expression in colorectal cancer cells.

    The study involved 23 healthy adults between the ages of 50 and 75 years old. Each participant followed two four-week-long dietary interventions (separated by a washout diet): a high-red meat diet (providing 300 grams of red meat daily – about three-fourths of a pound) and a high-red meat diet that also provided 40 grams of butyrylated resistant starch, a chemically modified form of resistant starch that is an effective vehicle for delivering butyrate to the colon. The investigators collected rectal tissue samples via biopsy at the completion of each intervention diet.

    After completing the high-red meat diet, the participants' rectal tissues exhibited a 30 percent increase in a cluster of microRNAs called microRNA 17-92, which participates in the cell cycle, proliferation, apoptosis (cell death), and other processes involved in cancer. But when the participants added resistant starch to their high-red meat diet, their microRNA 17-92 levels returned to baseline levels.

    These findings suggest that butyrylated resistant starch moderates the cancer-promoting effects of a diet high in red meat. Some of this benefit may arise from the delivery of butyrate. Learn more about butyrate in our overview article.

  • From the article:

    In a new study, published in Nature Immunology, researchers searched for alterations in the gut microbiome to see whether their metabolites could impact outcomes after BMT.

    They found that a metabolite called butyrate was significantly reduced in the intestinal tract of experimental mice that received bone marrow transplant. When the researchers increased butyrate in these mouse models, they saw a decrease in the incidence and severity of graft vs. host disease.

    “Our findings suggest we can prevent graft vs. host disease by bolstering the amount of the microbiome-derived metabolite butyrate,” says study lead author Pavan Reddy, M.D., the Moshe Talpaz Professor of Translational Pathology and interim division chief of hematology/oncology at the University of Michigan.

  • Currently selected for this coming member’s digest by team member Melisa B.

    From the article:

    Researchers report in the April issue of Cancer Research that the GPR109A receptor is activated by butyrate, a metabolite produced by fiber-eating bacteria in the colon. The receptor puts a double-whammy on cancer by sending signals that trigger cell death, or apoptosis, and shutting down a protein that causes inflammation, a precursor to cancer.

    […]

    That got the German research team to search for alternative activators of the receptor, resulting in identification of beta-hydroxybutyrate as a natural receptor activator. The same study showed butyrate also could activate the receptor but with much less potency. That got Dr. Ganapathy thinking about a place where butyrate levels were already high – the colon – which led to his discovery that the receptor was also on colon cells.

    Butyrate plays other protective roles in colon cancer. In 2004, MCG researchers identified a gene, SLC5A8, that transports butyrate inside cells where it inhibits the enzyme HDAC, which gets upregulated in cancer to produce the uncontrolled cell growth that is a disease hallmark.

    “If you block HDAC, you can kill the cancer cell,” Dr. Ganapathy says.

  • Beta-hydroxybutyrate reduces symptoms of gout.

    Gout is a painful, debilitating disease that affects more than 8 million people living in the United States. The condition arises when uric acid crystals form in and around the joints, causing inflammation, pain, and impaired mobility. Evidence from a 2017 study suggests that beta-hydroxybutyrate inhibits the activity of the NLRP3 inflammasome, reducing symptoms of gout.

    Beta-hydroxybutyrate is a type of ketone body. It forms in the liver via the breakdown of fatty acids and can be used to produce energy in the mitochondria. Beta-hydroxybutyrate also acts as a signaling molecule that alters gene expression via a wide range of molecular pathways. Ketogenic diets induce beta-hydroxybutyrate production.

    Inflammasomes are large, intracellular complexes that detect and respond to internal and external threats. Activation of inflammasomes has been implicated in a host of inflammatory disorders. The NLRP3 inflammasome, in particular, triggers the release of the proinflammatory proteins interleukin (IL)-1 beta and IL-18 and drives pyroptosis, a form of cell death that is triggered by proinflammatory signals and closely linked with inflammation.

    The study involved rats that are prone to developing gout. The investigators fed one group of the rats a normal diet and fed another group a ketogenic diet. After one week, they measured ketones present in the animals' urine. They found that the ketogenic diet induced production of beta-hydroxybutyrate, which in turn protected the animals against uric acid-induced elevations in IL-1 beta. Examination of the animals' joints revealed that the rats that ate the ketogenic diet had less joint inflammation than those fed a normal diet.

    Next, the investigators assessed the effects of beta-hydroxybutyrate on neutrophils, a type of immune cell, from both young and old humans. They found that the compound inhibited the NLRP3 inflammasome-induced IL-1 beta secretion in both young and old neutrophils, suggesting that the ketone plays a role in activating the inflammasome in neutrophils, regardless of age.

    These findings suggest that beta-hydroxybutyrate inhibits the activity of the NLRP3 inflammasome, reducing the symptoms of gout. Researchers do not know if these results translate to humans, however. Learn more about the health effects of beta-hydroxybutyrate in our overview article.

  • From the article:

    “Our team found that high salt consumption lowered levels of circulating beta hydroxybutyrate. When we put beta hydroxybutyrate back in the system, normal blood pressure is restored,” said Dr. Bina Joe, Distinguished University Professor and chair of UT’s Department of Physiology and Pharmacology and director of the Center for Hypertension and Precision Medicine. “We have an opportunity to control salt-sensitive hypertension without exercising.”

    The effects may be microbiome mediated. Read the following excerpt from discussion in a Cell spotlight:

    Changes in the microbiota, specifically a decrease in Lactobacillus spp., in rats fed a high-salt diet have also been implicated in drivingthe progression of hypertension. The authors found that Lactobacillus spp. and Proteobacteria were reduced and Prevotella spp. were increased by a high-salt diet. The changes in the microbiota were associated with a decrease in gluconeogenesis and ketone metabolism, which was not restored by supplementation with 1,3-butanediol. Interestingly, after 1,3butanediol treatment, Proteobacteria and Prevotella shifted back toward the low-salt relative abundance and also correlated with an increase in protective Akkermansia levels.

  • Inflammatory bowel disease (IBD) is an umbrella term for two chronic inflammatory conditions that affect the digestive tract – ulcerative colitis and Crohn’s disease. Symptoms of IBD include diarrhea, rectal bleeding, abdominal pain, fatigue, and weight loss. Evidence indicates that dysbiosis, an imbalance in the types and numbers of microbes in the gut, contributes to the pathogenesis of IBD. And now, findings from a recent study suggest that eating a high-sugar diet promotes dysbiosis and the development of IBD.

    The study involved normal mice and mice that are genetically predisposed to develop colitis. The authors of the study gave a subset of both groups of mice a 10 percent glucose solution (comparable to a sugar-sweetened soft drink) for one week. They gave the normal mice a chemical that causes colitis. Then they measured the inflammatory responses, disease severity, and gut microbial composition in both groups of mice and compared them to mice that did not receive the sugar solution.

    They found that, prior to the mice developing colitis, the sugar did not trigger gut inflammation. However, both groups of mice developed worse symptoms of colitis after drinking the glucose solution. In addition, both groups exhibited higher numbers of bacteria that break down the mucus layer of the gut (specifically, Akkermansia muciniphila and Bacteroides fragilis), contributing to mucus layer destruction, increasing gut permeability. The number of beneficial bacteria in the animals' guts decreased, however.

  • Inflammation, a critical element of the body’s immune response, occurs when the body is exposed to harmful stimuli, such as pathogens, damaged cells, or irritants. As a person ages, their immune system becomes more pro-inflammatory, leading to unresolved or chronic inflammation and driving many age-related diseases and cognitive decline. Authors of a new report suggest that eating a pro-inflammatory diet may further contribute to the inflammatory state associated with aging, driving cognitive decline.

    Diet plays key roles in immune function and inflammation, and robust evidence indicates that some components of diet promote inflammation, while others dampen or even resolve it. To score the inflammatory potential of dietary components, researchers have developed the Diet Inflammatory Index, a quantitative means of assessing the effects of diet on aspects of human health, ranging from inflammatory biomarkers in blood to the presence of chronic disease. The Index, which has been used in hundreds of studies and meta-analyses, is supported by diverse lines of evidence, including laboratory, observational, and interventional studies.

    The authors recruited more than 1,000 older adults (average age, 73 years) who were enrolled in the Hellenic Longitudinal Investigation of Aging and Diet study. They collected detailed information about the types and quantities of the foods that participants regularly ate and assigned each participant’s diet a Diet Inflammation Index score. They tracked the participants for about three years and noted whether they were diagnosed with dementia.

    They found that for every unit increase in the Diet Inflammation Index, the risk for developing dementia increased by 21 percent. As a result, participants whose diets had the highest inflammatory potential were three times more likely to develop dementia than those whose diets had the lowest inflammatory potential.

    These findings suggest that dietary components modulate the inflammatory state associated with aging and drive the risk for developing dementia. Although these findings were based on observational data and do not assign causality, they highlight the roles that lifestyle changes may play in preserving cognitive function in aging. Learn more about how lifestyle changes can influence health and slow the effects of aging in this episode featuring Dr. Elisa Epel.

  • Nutrient sensing – a cell’s capacity to recognize and respond to fuel sources – plays a critical role in human health, ultimately influencing the aging process and susceptibility to age-related disease. Findings from a recent study suggest that dietary interventions exert powerful effects on proteins produced in the liver, fundamentally “reprogramming” nutrient-sensing pathways.

    Multiple studies have investigated the possibility that dietary strategies or drugs can alter nutrient-sensing pathways to improve metabolic health and extend lifespan. For example, robust evidence indicates that intermittent fasting and calorie restriction prolong lifespan in rodents and monkeys. Other findings suggest that altering dietary composition, such as increasing or decreasing protein, fat, or carbohydrate content, also influences longevity. Similarly, many drugs and bioactive compounds have demonstrated longevity-promoting qualities.

    The study investigators assessed the effects of various diets and drugs on liver protein production in mice, using the Geometric Framework for Nutrition, a research tool that identifies links between diet, health, and disease. Diets included in the analysis varied in terms of overall nutrient content and calories. Drugs under study included metformin (an anti-diabetes drug), rapamycin (an anti-parasitic drug), and resveratrol (a bioactive compound derived from certain fruits and vegetables).

    Diets with lower caloric content accelerated production of proteins required for overall protein synthesis (particularly genes for a cellular machine called the spliceosome). As dietary protein content increased, oxidative stress in mitochondria increased. Higher protein content also increased SLC25A51, a cellular protein involved in the transport of nicotinamide adenine dinucleotide (NAD+). NAD+ participates in many aspects of metabolism, and its depletion has been implicated in the onset and progression of metabolic dysregulation. Interestingly, anti-aging drugs diminished the effects of diet. For example, metformin and rapamycin impaired mitochondrial responses to protein, and resveratrol decreased the response to fats and carbohydrates.

    These findings suggest that diet dramatically influences cellular processes involved in metabolism and longevity and is superior to current anti-aging drugs and compounds. Learn more about dietary strategies, drugs, and bioactive compounds that may promote longevity in our overview articles about caloric restriction, time-restricted eating, metformin, and resveratrol.

  • A diet rich in plant foods, lean protein, and healthy fat is associated with a reduced risk of death from cardiovascular disease, cancer, and all causes; however, many of the cellular and molecular mechanisms of these relationships are unknown. One of the mechanisms that controls a person’s response to diet and risk of disease is epigenetic modification. Findings of a new investigation detail the relationship between healthy eating and epigenetic and biological age.

    While a person’s genetic code does not change over time, the pattern of epigenetic markers attached to DNA does change with age. Epigenetic modifications include the addition and subtraction of methyl groups, naturally occurring processes that regulate gene expression. These changes are quantifiable and serve as a means to gauge biological age, which is often different from chronological age. Epigenetic aging clocks use an organism’s DNA methylation profile biomarker of aging based on alterations in an organism’s DNA methylation profile and can be used to predict likelihood of death (i.e., mortality).

    The investigators utilized data from the Sister Study, an observational study of over 50,000 females in the United States who had a biological sister diagnosed with breast cancer, but were free from cancer themselves. These participants provided data about their dietary habits and provided a blood sample for the measurement of epigenetic age and other factors. Next, the authors analyzed the diet data and calculated four scores of diet quality that aligned with dietary recommendations from the USDA and other sources. The authors analyzed a subsample of almost 3,000 participants in order to calculate epigenetic age using the Hannum, Horvath, PhenoAge, and GrimAge clocks.

    The data revealed only a weak association between higher diet quality and epigenetic age as measured by the two aging clocks designed as predictors of chronological age (Horvath and Hannum clocks). However, there was a strong relationship between diet quality and epigenetic age calculated by the two clocks designed to estimate mortality (PhenoAge and GrimAge clocks). This highlights the differences between aging clock designs, but it also supports a relationship between diet quality and disease risk that is mediated by epigenetic changes. The relationship between increased diet quality and reduced mortality-related epigenetic age was strongest among participants who did not meet exercise recommendations. Smoking status and age did not significantly alter these statistical relationships.

    These findings demonstrate that higher diet quality is associated with a lower biological age as estimated by epigenetic clocks designed to predict mortality. Learn more about epigenetics from expert Dr. Steve Horvath, creator of the Horvath epigenetic aging clock, in this episode of the FoundMyFitness podcast.

  • Seventy percent of adults living in the United States have overweight (BMI greater than 25) or obesity (BMI greater than 30), putting them at increased risk of metabolic disease. Extra fat stored around the body promotes inflammation and insulin resistance, but extra abdominal fat is particularly dangerous. Findings of a recent report suggest consuming foods rich in unsaturated fat and dietary fiber may improve fat distribution in females.

    Fat stored in the lower body, called subcutaneous fat, is located just under the skin. Fat stored in the abdominal region, called visceral fat, is wrapped around the internal organs (e.g., the liver, pancreas, and intestines). Visceral fat interferes with lipid metabolism in the liver, promoting insulin resistance, type 2 diabetes, and non-alcoholic fatty liver disease. A diet that includes avocados, which are rich in mono-unsaturated fats and dietary fiber, is associated with lower abdominal obesity.

    The investigators recruited 105 adults between the ages of 25 and 45 years who had overweight or obesity. They assigned participants to receive meals with avocado (about one Hass avocado) or meals without avocado that were matched for calories and total fat. The two meals contained different amounts of saturated fat, unsaturated fat, and fiber. Participants consumed their assigned meals once per day for 12 weeks and were told not to change their diet in other ways. Participants completed an oral glucose tolerance test to measure insulin resistance and had their body composition measured using X-ray.

    In females, avocado consumption decreased visceral adiposity and the ratio of visceral to subcutaneous fat, indicating an improvement in body fat distribution. Both males and females in the control group experienced a loss of subcutaneous fat and an increase in the ratio of visceral to subcutaneous fat, indicating a worsening of body composition over the 12 weeks. Avocado consumption had no effect on insulin resistance.

    The authors concluded that avocado consumption improved body fat distribution in females, but had no effects on body fat distribution in males or on insulin resistance in either males or females.

  • Redefining the causes of obesity. www.sciencedaily.com

    Obesity is a complex, multifactorial disease influenced by genetic, molecular, environmental, and behavioral factors. Characterized as having excessive body fat, obesity affects more than 650 million people worldwide and markedly increases a person’s risk for many chronic diseases, including cardiovascular disease, type 2 diabetes, cancer, and depression, among others. The authors of a recent report challenge the prevailing theory regarding the root causes of obesity.

    A widely espoused concept in bodyweight management is the “eat less, exercise more” model, based on the principle that the number of calories consumed must be equivalent to (or less than) the number of calories expended. This model is supported by evidence suggesting that consuming high-fat foods drives overconsumption of calories due the foods' high caloric levels, poor ability to provide satisfaction and fullness, and high “pleasure factor.” However, this concept, which forms the basis for national dietary guidelines, public health messaging, and dietary counseling, is inherently flawed, because it fails to take into consideration the biological mechanisms that promote weight gain. Ultimately it places blame on people with obesity and promotes stigmatization.

    In recent decades, scientists have proposed a new model for explaining the root causes of obesity. In this model, body fat accumulation arises from hormonal responses to the consumption of high-glycemic load carbohydrates, ultimately driving a vicious cycle of body fat accumulation, hunger, and food intake. Commonly referred to as the “carbohydrate-insulin” model of obesity, this new paradigm reverses causation and provides a starting point for developing testable hypotheses.

    The concepts presented in this report suggest that what a person eats, rather than how much, plays key roles in body weight management. The authors of the report posited that if the carbohydrate-insulin model is accurate, dietary modifications that limit carbohydrate intake, such as a ketogenic diet, may alter hormonal responses and promote fat oxidation and weight loss. Learn more about the health benefits of the ketogenic diet in this clip featuring Dr. Dominic D'Agostino.

    Link to full publication.

  • Aging induces a number of disease-related changes to the cardiovascular system, including dysfunction of the endothelial cells that line blood vessels. Eating fruits and vegetables, which are rich in a variety of beneficial bioactive compounds, may slow cardiovascular aging. Investigators tested the effects of anthocyanin compounds from blueberries on flow-mediated dilation.

    Flow-mediated dilation refers to the capacity of an artery to expand in response to increased blood flow. It is a widely accepted measure of vascular endothelial function, and poor flow-mediated dilation is a recognized feature of cardiovascular disease. Previous research has demonstrated a relationship between higher blueberry and strawberry intake and decreased risk of heart attack. Blueberries contain a number of bioactive compounds, including anthocyanins, procyanidins, flavonols, phenolic acids, and other phenolic compounds. The body subjects these compounds to a wide range of chemical processes, yielding bioactive metabolites. How these bioactive compounds differ in their effects on cardiovascular health is unclear.

    The authors analyzed data from four studies involving a total of 60 participants and conducted a follow-up experiment in mice. In the first study, participants received one of five treatments on five separate days: a control beverage that mimicked blueberry juice; the control beverage with fiber added; the control beverage with added minerals and vitamins; pure anthocyanins; and a beverage made with freeze-dried blueberries. The investigators measured flow-mediated dilation at baseline and one, two, and six hours after participants ingested the beverages. In the second study, participants consumed capsules containing one of six concentrations of anthocyanins (0, 80, 160, 240, 320, or 480 milligrams) on six separate days. The investigators measured flow-mediated dilation at baseline and two and six hours after ingestion.

    The third study measured the effects of long-term blueberry consumption. Participants consumed 11 grams of wild blueberry powder (equivalent to about four ounces of fresh blueberries) dissolved in water twice daily for 28 days. The investigators measured flow-mediated dilation at baseline and at seven, 14, 21, and 28 days of consumption. In the fourth study, participants consumed a drink containing 11 grams of wild blueberry powder or a control beverage twice daily for at least 28 days. The investigators measured flow-mediated dilation at baseline and two hours after ingestion on the first day of the intervention and after at least 28 days of consumption. For the follow-up experiment, investigators gave mice an injection of bioactive metabolites that they had identified from the previous human experiments and measured the effects on flow-mediated dilation.

    Isolated anthocyanins improved endothelial function as measured by flow-mediated dilation in a dose-dependent manner, meaning that the effects were more robust as dose increased. The effects of these isolated anthocyanins were similar to those of wild blueberries. However, control beverages containing fiber, minerals, or vitamins and minerals had no significant effect on flow-mediated dilation. Twice daily wild blueberry consumption for one month also increased long-term flow-mediated dilation. Finally, injection of metabolites derived from the phenolic compounds found in blueberries improved flow-mediated dilation in mice.

    These results demonstrate the beneficial effects of blueberries on cardiovascular health and elucidates the function of anthocyanin compounds as major mediators of vascular function in mice and humans.

  • Aging impairs the body’s ability to fight infection due to chronic low-grade inflammation and a decrease in antibody-producing T cells. Consequently, 80 percent of deaths due to COVID-19 in the United States have been among adults 65 years of age and older. Researchers investigated the use of a ketogenic diet in mice as a strategy for treating COVID-19.

    A ketogenic diet is a high fat, low carbohydrate diet. Adherence to a ketogenic diet reduces blood glucose levels, which are associated with increased inflammation. Adopting a ketogenic diet may be an effective strategy for limiting excessive inflammation, especially in older adults, who are more likely to have poor blood glucose control.

    The SARS-CoV-2 virus, the cause of COVID-19 illness, induces lung inflammation. In severe cases, patients may need mechanical ventilation to breathe and may have long-lasting respiratory problems after recovery. Previous COVID-19 research has shown that white blood cells such as neutrophils and monocytes accumulate in the lungs. There they become more reliant on glucose, accelerate their mitochondrial metabolism, and produce more damaging oxidative compounds, contributing to unchecked inflammation and disease severity.

    The researchers used mice that express the human angiotensin-converting enzyme (ACE) 2 receptor, which is the point of entry for the SARS-CoV-2 virus in the lungs and other organs. They fed young adult mice and older adult mice either a standard diet or a ketogenic diet for five days before exposing them to a hepatitis virus that closely mimics the SARS-CoV-2 infection in humans. The mice continued their assigned diet for an additional seven days following infection. The investigators measured markers of inflammation and metabolic function.

    Older mice had significantly higher levels of inflammation and metabolic dysfunction at the beginning of the study. Upon infection, they had greater inflammation in the heart, adipose tissue, and hypothalamus; worse pneumonia symptoms and increased blood clot formation; and were more likely to die due to infection, compared to younger mice. The increased inflammation was due to an increase in neutrophil accumulation and a decrease in tissue-protective T cells in the lungs. A ketogenic diet reprogrammed metabolism and the immune system to a greater extent in older mice by increasing the number of beneficial T cells and reducing the number of harmful monocytes in the lungs, leading to less inflammation overall and reduced disease severity.

    Although this study was conducted in mice, the authors concluded that a ketogenic diet may be a potential treatment for SARS-CoV-2 infection in older adults due to its ability to modulate immune function and dampen excessive inflammation.

  • Obesity is characterized by chronic low-grade inflammation, which contributes to the development of cardiovascular disease. While processed foods and beverages high in saturated fats and simple sugars are associated with a higher risk of cardiovascular disease, diets rich in plant-based foods, including fruits, are associated with a lower risk. Findings of a recent report detail the effects of daily apple consumption on inflammation, endotoxemia, and metabolism.

    Causes of obesity-associated inflammation include leaky gut, a condition where the intestinal barrier is compromised, leading to increased levels of bacterial endotoxin (toxins that are released when bacteria die) in the bloodstream (called endotoxemia). This increase in endotoxin levels activates white blood cells to secrete pro-inflammatory cytokines such as interleukin (IL)-6 and IL-17. Plant foods such as apples are beneficial for people with obesity because they are rich in bioactive compounds that decrease inflammation and dietary fibers that strengthen the gut barrier.

    The researchers recruited 46 participants with overweight and obesity and directed them to avoid foods and beverages rich in polyphenols and/or dietary fibers (e.g., coffee, vegetables, grains, beans, and red/purple/blue fruits) for two weeks. Next, they assigned half of the participants to consume three Gala apples per day for six weeks or to avoid apples. Both groups continued to eat a diet with limited polyphenols and dietary fibers. Participants provided blood samples for the collection of white blood cells and measurement of pro-inflammatory cytokines. After isolating the white blood cells, the researchers stimulated them with endotoxin and measured their response.

    Apple consumption decreased plasma C-reactive protein (a pro-inflammatory cytokine) by 17 percent, IL-6 by 12 percent, and endotoxin-binding protein by 20 percent compared with no apple consumption. White blood cells from participants who consumed apples secreted 28 percent less IL-6 and 11 percent less IL-17. While apple consumption increased total antioxidant capacity in blood by 10 percent, it had no effect on cardiovascular disease markers.

    These findings suggest that six weeks of daily Gala apple consumption helped mitigate inflammation in those consuming a diet low in polyphenols and fiber, a common feature of the Western diet pattern. Apple consumption may decrease cardiovascular disease risk in those with obesity, even without weight loss.

  • The Mediterranean dietary pattern, which is low in saturated fats and high in unsaturated fats, is widely-recognized as a heart-healthy diet when compared to the standard American dietary pattern, which is high in saturated fats. Red meat is traditionally minimized in the Mediterranean dietary pattern to less than 120 grams (about four ounces) per week - roughly the size of a small burger patty; however, this recommendation is largely based on epidemiological evidence, not interventional trials. Authors of a new report aimed to determine the dose-dependent effects of lean beef consumption as part of a Mediterranean dietary pattern on heart disease risk.

    Recent research suggests that lean, unprocessed red meat can be included in a heart-healthy dietary pattern. One randomized clinical trial found that consumption of a Mediterranean dietary pattern supplemented with 500 grams (about 17 ounces) of red meat per day over five weeks reduced total and LDL cholesterol.

    Fifty-nine generally healthy participants of varying weight status between the ages of 30 and 65 years completed the trial. Participants consumed a Mediterranean dietary pattern (8 percent saturated fat) supplemented with either 0.5, 2.5, or 5.5 ounces of lean, unprocessed beef per 2,000 calories consumed per day. As a comparison diet, participants also consumed an American dietary pattern (12 percent saturated fat). All participants consumed each diet for four weeks in a randomized order and had their blood drawn at multiple time points for cholesterol testing.

    Compared to the American dietary pattern, all three Mediterranean dietary patterns significantly reduced LDL cholesterol (0.5 ounces: −10.3 milligrams per deciliter; 2.5 ounces: −9.1 milligrams per deciliter; 5.5 ounces: −6.9 milligrams per deciliter). The authors also reported reductions in LDL particle number for all three Mediterranean dietary patterns, although this reduction was significant for the diets supplemented with 0.5 ounces or 2.5 ounces of red meat but not 5.5 ounces. All four diets resulted in reductions of HDL cholesterol and HDL particle number compared to baseline.

    The researchers concluded that the cholesterol-lowering effects of a Mediterranean dietary pattern were not diminished by the inclusion of up to 2.5 ounces of lean, unprocessed beef. They noted that future research should test a similar diet in patients with worse health status than this generally healthy population.

  • A healthy gut microbiota is important for cognitive function at any age, but especially during development. Poor dietary quality in early life (i.e., consuming excess sugar) negatively impacts the composition of the gut microbiota and impairs cognitive functioning; however, the mechanisms that drive these changes are unclear. Authors of a new report detail the functional relationship between detrimental gut microbes and hippocampal memory in rats exposed to excess sugar during adolescence.

    Germ-free mice, which are born and raised in a sterile environment, demonstrate impaired brain development compared to mice with a normal gut microbiota. This suggests that microbiota composition in early life may impact cognitive function in adulthood. Dietary strategies that minimize sugar intake may improve microbiota quality and maximize developmental potential in children and adolescents.

    The investigators conducted a two-part experiment in rats. In the first experiment, they fed sugar-sweetened water or plain water to juvenile rats for 11 weeks. They sequenced bacterial DNA from the rats' fecal samples to measure changes in the gut microbiota. In the second experiment, the researchers treated juvenile rats with antibiotics or a placebo for seven days. Then they treated one half of the antibiotic group with a bacterial culture of Parabacteroides distasonis and Parabacteroides johnsonii, while the other half received a placebo. In both experiments, rats completed a series of tests to measure memory function in adulthood. Finally, the researchers measured gene expression in the hippocampus, one the major memory centers of the brain.

    Adult sugar-fed rats exhibited impaired performance on memory tasks associated with the hippocampus, but not other memory centers. The authors discovered that sugar consumption led to an increase in Parabacteroides bacteria in the gut that correlated with impaired hippocampal function. When antibiotic-treated rats were given Parabacteroides distasonis and Parabacteroides johnsonii as a supplement in adolescence, they exhibited similar deficits in memory performance in adulthood as sugar-fed rats. Sugar consumption altered the expression of genes associated with neurotransmitter signaling, while Parabacteroides treatment altered genes associated with metabolic function, neurodegenerative disease, and dopamine signaling.

    The authors of this comprehensive report concluded that early-life dietary factors like sugar consumption impact brain development and may impair memory via changes in the gut microbiota.

    Link to full study.

    Learn more about sugar and its effects on the brain and body in this podcast featuring Dr. Rhonda Patrick.

  • Whole grains are rich in dietary fiber, vitamins, and minerals. Robust evidence indicates that people who consume whole grains as part of a healthy diet are less likely to develop cancer or cardiovascular disease or die prematurely. However, findings from a recent study suggest that consumption of refined grains increases a person’s risk of cardiovascular disease and premature death.

    Refined grains are processed to remove the bran and germ, imparting a finer texture to the grains and extending their shelf life. The refining process also removes many vitamins, minerals, and dietary fiber. Examples of refined grains include white flour and white rice. Refined grains are used to make many processed foods, such as white bread, breakfast cereals and pastries, and baked desserts. Evidence suggests that refined grain consumption is linked with higher levels of atherogenic small, dense LDL particles](https://jamanetwork.com/journals/jama/article-abstract/185711).

    The authors of the new study drew on data from a diverse population of more than 137,000 people living in 21 low, middle, and high income countries enrolled in the Prospective Urban and Rural Epidemiology study. Participants completed questionnaires about their socioeconomic status, health, physical activity, and diet.

    Analysis of the questionnaires revealed that eating 350 grams or more (about seven servings) of refined grain products per day, such as white bread, noodles, breakfast cereals, crackers, and bakery products, increased a person’s risk of stroke by 47 percent, cardiovascular disease by 33 percent, and premature death by 27 percent. Eating whole grains and rice did not increase risk.

    These findings suggest that consumption of refined grains increases a person’s risk of cardiovascular disease and premature death. However, this was an observational study and did not establish causation. The data were adjusted to account for several possible confounding factors such as body composition, physical activity, and socioeconomic status, but other factors could be at play.

  • Carotenoids are red, yellow, and orange pigments found in fruits and vegetables that exert antioxidant, anti-inflammatory, and anticancer properties. Lycopene (which is found in tomatoes and watermelon) and lutein (which is found in green leafy vegetables) are among the most abundant carotenoids in the human diet. Findings from a recent study suggest that consuming vegetables that are high in lycopene and lutein can help reduce visceral fat in obese men.

    Visceral fat is body fat that is stored in the abdominal cavity close to internal organs such as the liver, pancreas, and intestines. In contrast to subcutaneous fat, which is located under the skin, visceral fat plays a central role in the interrelationship between obesity and systemic inflammation through its secretion of proinflammatory cytokines. The accumulation of visceral fat is linked to type 2 diabetes, insulin resistance, inflammatory diseases, certain types of cancer, cardiovascular disease, and other obesity-related diseases.

    The randomized, double-blinded, controlled clinical trial involved 28 men between the ages of 40 and 65 years who were overweight or obese. The authors of the eight-week study randomly assigned the participants to consume a beverage containing one of four edible pastes that contained high lycopene/high lutein; high lycopene/low lutein; low lycopene/high lutein; or low lycopene/low lutein. The authors measured the levels of carotenoids in the participants' plasma.

    The participants' carotenoid levels increased in every group and they experienced no adverse effects. Their visceral fat levels decreased for all groups, too, but waist circumference decreased only for the men in the high lycopene/low lutein group.

    These findings suggest that high carotenoid intake can help with weight loss. They also support epidemiological data indicating that vegetable intake can play a positive role in modulating body weight. For a tasty way to include more carotenoids in your diet, check out this video in which Dr. Rhonda Patrick shows how to make her carotenoid-rich smoothie.

  • β-hydroxybutyrate production consequent to exercise induces within the muscle the activities of a key promoter involved in the production of brain-derived neurotrophic factor.

    From the article:

    Studies have shown that BDNF levels in the brains of people with Alzheimer’s or Huntington’s disease are, on average, half that of people without either brain-damaging disease.

    Among the key findings of the current study was that a ketone, a chemical naturally produced in the liver called beta-hydroxybutyrate (DBHB), triggers biological reactions that activate the BDNF gene to produce more of its protein. DBHB has long been known to build up in the body and brain with exercise. Ketones are “by-product” chemicals made when animals break down fat as an alternative energy source after having drained more readily available sugar stores during exercise.

    Specifically, Chao says, the researchers found that DBHB prevents other proteins in the brain known as histone deacetylase complexes, or HDACs, from suppressing BDNF production by altering the environment of the BDNF gene.

  • Chemotherapeutic agents, powerful drugs used in cancer treatment, kill cancer cells but can also damage healthy cells. Chemotherapy administered to shrink a tumor prior to surgery is known as neoadjuvant chemotherapy. Findings from a recent study suggest that following a fasting-mimicking diet before neoadjuvant chemotherapy impacts both the toxicity and efficacy of the treatment.

    A large body of evidence indicates that prolonged fasting can reduce the risk of chronic diseases by improving overall metabolic health. A fasting-mimicking diet, or FMD, is designed to achieve effects similar to a multiple day water-only fast while being easier to follow.

    Previous preclinical research has demonstrated that prolonged fasting sensitizes cancer cells to chemotherapy while protecting healthy cells. Studies in animal models indicate that during prolonged fasting, healthy cells shift to a resting metabolism that protects them from nutrient scarcity; however, cancer cells are unable to do this. The current study investigated whether the fasting-mimicking diet influenced the toxicity or effectiveness of chemotherapy in women with early-stage breast cancer.

    The authors of the randomized controlled study assigned 131 women with stage II/III breast cancer to receive either an FMD or their regular diet three days before and throughout neoadjuvant chemotherapy. Both groups of women experienced similar side effects, despite the fact that only those on the regular diet were given dexamethasone — a drug to lessen side effects. The authors suggest that these findings might eliminate the need for drugs to manage side effects. Researchers observed that women on the FMD were more likely to experience a 90 to 100 percent tumor cell loss as compared to women on a regular diet. Furthermore, patients on the FMD had less DNA damage in T-lymphocytes from chemotherapy than those on the regular diet.

    These findings suggest that an FMD can curb damage to normal cells while increasing a cancer cell’s vulnerability to chemotherapy in women with breast cancer. Further clinical trials will determine if fasting or an FMD in conjunction with standard of care will be helpful in the treatment of other cancers.

  • Cardiovascular disease is a broad class of diseases that involve the heart or blood vessels, including stroke, hypertension, thrombosis, heart failure, and atherosclerosis. As much as 90 percent of cardiovascular disease may be attributable to lifestyle factors and, therefore, preventable. A recent study found that having better cardiovascular health during one’s midlife years may reduce risk of premature death later in life.

    The American Heart Association has developed a scoring system that describes a person’s cardiovascular health based on measures of various lifestyle behaviors, such as smoking, diet, and physical activity, and known cardiovascular disease risk factors, such as blood pressure, body mass index, and blood glucose and cholesterol levels. Having a higher cardiovascular health score is associated with reduced markers of disease, longer telomeres, and better vascular function and, consequently, lower risk of cardiovascular disease, diabetes, and premature death.

    The prospective cohort study, which spanned a 16-year period, drew on data from the Framingham Heart Study Offspring investigation and involved 1,445 men and women whose average age was 60 years. The authors of the study found that for every five-year period that a person had intermediate or ideal cardiovascular health, they had a 33 percent lower risk for high blood pressure, 27 percent lower risk for diabetes or cardiovascular disease, 25 percent lower risk for diabetes, and 14 percent lower risk for premature death, compared to people who were in poor cardiovascular health. These findings held true regardless of age or sex.

    Sauna use is a lifestyle behavior that has been shown to improve cardiovascular health. A large study of health outcomes in more than 2,300 middle-aged men from eastern Finland identified strong, dose-dependent links between sauna use and reduced cardiovascular-related death and disease. Compared to men who used the sauna once weekly, men who used the sauna four to seven times per week were 50 percent less likely to die from cardiovascular-related causes. Watch this clip in which Drs. Rhonda Patrick and Jari Laukkanen discuss these findings.

  • The average life expectancy of people living in the United States is roughly 79 years. Several factors influence how long a person lives, however, such as diet, physical activity, and smoking. A new study suggests that mental stress shortens life expectancy by nearly three years.

    Mental stress can affect the immune, digestive, cardiovascular, sleep, and reproductive systems, eliciting a wide range of symptoms, including headaches, sleeplessness, sadness, anger, or irritability. Prolonged stress can promote continued strain on the body, contributing to serious health problems, such as heart disease, high blood pressure, diabetes, and other illnesses, including mental disorders such as depression or anxiety.

    The study was based on data drawn from cross-sectional health surveys conducted every five years in Finland, spanning a 20-year period between 1987 and 2007 and including approximately 35,000 adults. The study participants were generally healthy and were between the ages of 25 and 74 years. The authors of the study conducted a statistical analysis of death rates using a model that included risk factors commonly associated with longevity, such as socioeconomic background, medical history, lifestyle, lifestyle satisfaction, and biological risk factors.

    They found that some factors decreased the risk of premature death such as eating fruits and berries daily or almost daily (15 percent lower), having a higher level of education (10 percent lower), or frequent engagement in leisure-time physical activity (25 percent lower). Factors that increased risk included smoking (67 percent higher) or having diabetes (100 percent higher), both of which correlated to nearly seven years' shorter lifespan. Having high levels of stress decreased lifespan among men by nearly three years.

    To learn more about the harmful effects of stress, watch this clip featuring Dr. Elissa Epel in which she describes how stress can modulate telomere length, a marker of aging.

  • Frailty is a syndrome that commonly manifests in older adults. It carries an increased risk for poor health outcomes including falls, disability, hospitalization, and death. A key driver in the development of frailty is inflammation, which often accompanies diet-induced changes in the gut microbiota. Findings from a recent study suggest that eating a Mediterranean diet, which is rich in fruits, vegetables, legumes, fish, and fiber, and low in saturated fat and red meat, alters the gut microbiome in older adults to reduce the risk of frailty.

    The intervention study involved more than 600 older, non-, pre-frail, or frail older adults living throughout Europe. Roughly half of the participants followed a Mediterranean diet for one year, while the other half, which served as the control group, ate their regular diets. Before and after the one-year intervention, the authors of the study profiled the microbial makeup of the participants' gut microbiome. Whereas the microbiome of the participants from the northern European countries shared many similarities, the participants from Italy had a distinct microbiome.

    At the end of the study, the participants who adhered to the Mediterranean diet showed reductions in biomarkers associated with inflammation (such as C-reactive protein and interleukin 17) and improvements in frailty-associated measures (such as handgrip strength, gait speed time, and cognitive function). The authors of the study observed notable changes in the participants' gut microbiomes, which were associated with higher numbers of bacteria that produce short-chain fatty acids – byproducts of dietary fiber metabolism that reduce gut inflammation.

    These findings suggest that dietary interventions that promote adherence to a Mediterranean diet may be beneficial in reducing the risk of developing frailty among older adults due to changes in gut microbiota and reduced inflammation.

    Interestingly, some of the benefits observed among the participants in this study may be related to their increased intake of essential vitamins and minerals. Without these nutrients, the body has to compensate for the shortages – a concept known as “triaging.” Long-term compensation contributes to aging. Watch this clip in which Dr. Bruce Ames explains this phenomenon in what he calls his triage theory.

  • The Western Style Diet, sometimes referred to as Standard American Diet (SAD), is a dietary pattern characterized by high intake of refined carbohydrates, fatty meats, added fats, and sodium, and low intake of whole grains, fruits, and vegetables. The Western dietary pattern has been implicated in the pathogenesis of many chronic diseases and conditions, including overweight and obesity, type 2 diabetes, high blood pressure, and heart disease. Findings from a recent study suggest that the Western dietary pattern impairs hippocampus-dependent learning and memory and drives loss of appetite control.

    The hippocampus is a small organ located within the brain’s medial temporal lobe. It is associated primarily with memory (in particular, the consolidation of short-term memories to long-term memories), learning, and spatial navigation. Data from rodent studies suggest that adherence to a Western dietary pattern impairs hippocampal-dependent learning and memory (HDLM). The hippocampus also plays a role in food intake by regulating appetite. Altered hippocampal function subsequent to exposure to a Western-style diet may create a vicious cycle state that promotes increased consumption of unhealthy foods that, in turn, drives further hippocampal dysfunction.

    The study involved 110 lean, healthy Australian adults between the ages of 17 and 35 years who adhered to a healthy, non-restrictive dietary pattern. The authors of the study randomized the participants to either a one-week Western-style diet intervention group or a habitual-diet control group.

    On the first and eighth days of the study, the participants in the Western diet group ate a breakfast that included a toasted sandwich and a milkshake (high in saturated fat and added sugar). On the second through seventh days of the study, the participants ate two Belgian waffles for either breakfast or dessert for four of the study days. On the other two study days, they obtained their main meal and a drink or dessert from a set of options from a popular fast-food chain. They followed their normal dietary pattern for all other meals. The participants in the control group ate a breakfast consisting of a toasted sandwich and a milkshake (low in saturated fat and added sugar) on the first and eighth days and followed their normal diet for all other meals.

    The authors of the study assessed the participants' HDLM function as well as their appetite control before and after the intervention and control periods and again at a three-week follow-up assessment. They found that among those who followed the Western-style diet, HDLM performance declined, compared to the control group. Their appetite control declined as well, and this was strongly correlated with HDLM decline.

    These findings suggest that even short-term consumption of a Western-style diet may impair learning and appetite control due to impaired hippocampal function. This lack of appetite control could promote overeating and drive weight gain.

  • Roughly two-thirds of all adults living in the United States are overweight or obese. Losing weight presents many challenges, however, and popular weight-loss diets and dietary patterns are not always successful or sustainable. A recent study found that people who followed an intermittent fasting, Mediterranean, or Paleo diet lost weight and showed improvements in health, but adherence to the diets varied.

    Intermittent fasting is a broad term that describes periods of fasting between meals that can last several hours to days. Intermittent fasting increases the production of ketones due to the use of stored fat as an energy source. It also activates some of the same genetic pathways as caloric restriction. The authors of this study defined intermittent fasting as 25 percent of the participants' usual dietary intake two days per week.

    The Mediterranean diet is a dietary pattern thought to confer health benefits found traditionally in Mediterranean countries. It is characterized by high consumption of vegetables, olive oil, and dairy products and moderate consumption of protein. The Paleo diet is based mainly on foods presumed to be available to Paleolithic humans. It includes vegetables, fruits, nuts, roots, meat, and organ meats and excludes dairy products, grains, refined sugar, legumes, and other processed foods. The authors of this study modified the typical Paleo plan to include limited consumption of dairy, legumes, and grains.

    The study mimicked “real world” dieting strategies in that each participant could choose which of the three dietary patterns they would follow for 12 months. In addition, they received no nutritional counseling other than a single, 30-minute session in which they learned about their self-selected diet. The authors of the study collected information about the participants' dietary intake, body weight and composition, blood pressure, physical activity, and various blood biomarkers, including glycated hemoglobin, a measure of long-term blood glucose control (also known as HbA1c).

    Approximately 54 percent of the participants chose to follow the intermittent fasting diet, 27 percent chose the Mediterranean diet, and 18 percent chose the Paleo diet. At the end of the 12-month study period, adherence to the three diet plans was 54 percent for intermittent fasting, 57 percent for the Mediterranean, and 35 percent for Paleo.

    Study participants lost weight with all three plans, but those who practiced intermittent fasting lost more (4 kg) than those who followed the Mediterranean (2.8 kg) or Paleo diets (1.8 kg). Those who followed the intermittent fasting and Mediterranean diet plans showed reductions in blood pressure (4.9 mm Hg and 5.9 mm Hg, respectively). Those who followed the Mediterranean diet experienced a 0.8 mmol/mol reduction in HbA1c.

    These findings suggest that people can lose weight and improve health while following different dietary patterns as long as those patterns include healthful foods and are personally sustainable.

  • Breast cancer is one of the leading causes of death among women living in the United States, claiming the lives of approximately 41,000 women each year. Being overweight or obese increases a woman’s risk of developing breast cancer. Findings from a new study indicate that women who lose weight after the age of 50 years and keep the weight off have reduced risk of developing breast cancer.

    More than two-thirds of women living in the United States are overweight or obese. Excess body fat increases a person’s risk for developing type 2 diabetes, a known risk factor for cancer. Body fat also alters hormone levels, which may increase the risk of developing hormone-sensitive cancers, such as breast cancer. In addition, body fat secretes a wide array of pro-inflammatory substances that damage DNA and inhibit apoptosis.

    The study involved more than 180,000 women who were 50 years of age and older from cohorts of 10 different prospective studies. The women were weighed three times over a period of 10 years. Those who lost weight and kept it off had a lower risk of breast cancer than women who did not lose weight.

    Among women who lost 4 to 10 pounds, 10 to 20 pounds, or 20 or more pounds, risk decreased by 13 percent, 16 percent, and 26 percent, respectively. Among women who lost 20 or more pounds but gained a portion of the weight back, risk was reduced by 23 percent.

    These findings point to the importance of public health interventions that promote weight loss among women as a means to reduce cancer risk.

  • Low-density lipoproteins (LDL) are formed in the liver and transport lipid molecules to cells. Often referred to as the “bad cholesterol,” LDL can drive cardiovascular disease if it becomes oxidized within the walls of arteries. LDL particles exist in different sizes, ranging from large, “fluffy” molecules to small, dense molecules. Scientific evidence suggests that small, dense LDL particles are more susceptible to oxidative modification. Findings from a new study suggest that diets that include avocados may help reduce LDL oxidation.

    The randomized, controlled trial involved 45 men and women between the ages of 21 and 70 years. The participants, who were overweight or obese and had elevated LDL cholesterol levels, followed three different diets for a period of five weeks each: a low-fat diet, a medium-fat diet with avocado, and a medium-fat diet with oleic acids (found in olive and canola oils).

    Avocados are rich sources of monounsaturated fatty acids. They also contain polyphenols and lutein, a carotenoid compound that quenches and scavenges reactive oxygen species.

    After five weeks on the diet with avocado, the participants' levels of oxidized LDL cholesterol (especially the small, dense LDL cholesterol particles) were lower than their baseline levels or after completing the low- or moderate-fat diets. Concentrations of large, fluffy LDL particles were unchanged. Participants also had higher levels of lutein. These findings suggest that consuming avocados as part of an overall heart-healthy diet may reduce the risk of developing cardiovascular disease.

  • For the last year and a half, I have been on a ketogenic diet. Admittedly, it was heavy on saturated fat from dairy. Recently discovered that I have hypofunctioning PPAR-alpha genetics. Which now makes perfect sense because I could never get my ketones above 1 mmol, and my LDL skyrocketed (~190 on NMR, 86 when not in ketosis). Obviously, there were negatives to that dietary approach for me, but there were also a lot of positives. Not to mention, I would like to take advantage of the potential for longevity, decreasing cancer risk, etc that the ketogenic diet holds. Since learning this info (on top of the not so stellar labs), I have transitioned to a more Mediterranean diet with an emphasis on PUFA and MUFA. I’ve thought about doing periods of ketosis and fasting every now and then, while using PPAR-alpha agonists (like sesamin) to offset the genetic hypofunctioning. Would really like to get some insight on the safety, efficacy, etc of doing this.

  • Transition metals are required cofactors for many proteins that are critical for life, and their concentration within cells is carefully maintained to avoid both deficiency and toxicity. To defend against bacterial pathogens, vertebrate immune proteins sequester metals, in particular zinc, iron, and manganese, as a strategy to limit bacterial acquisition of these necessary nutrients in a process termed “nutritional immunity.” In response, bacteria have evolved elegant strategies to access metals and counteract this host defense. In mammals, metal abundance can drastically shift due to changes in dietary intake or absorption from the intestinal tract, disrupting the balance between host and pathogen in the fight for metals and altering susceptibility to disease. This review describes the current understanding of how dietary metals modulate host-microbe interactions and the subsequent impact on the outcome of disease.

    https://www.cell.com/cell-host-microbe/fulltext/S1931-3128(18)30262-2

  • Loss of gut integrity is linked to various human diseases including inflammatory bowel disease. However, the mechanisms which lead to loss of barrier function remain poorly understood. Using D. melanogaster, we demonstrate that dietary restriction (DR) slows the age-related decline in intestinal integrity by enhancing enterocyte cellular fitness through upregulation of dMyc in the intestinal epithelium. Reduction of dMyc in enterocytes induces cell death through JNK signaling leading to increased gut permeability and reduced lifespan upon DR. Genetic mosaic and epistasis analyses suggest that cell competition, whereby neighboring cells eliminate unfit cells by apoptosis, mediates cell death in enterocytes with reduced levels of dMyc. Reducing enterocyte apoptosis partially rescued the increased gut permeability and shortened lifespan upon loss of dMyc. We propose that dMyc acts as a barometer of enterocyte cell fitness impacting intestinal homeostasis in response to changes in diet and age.

    Akagi, Kazutaka and Wilson, Kenneth A. and Katewa, Subhash D. and Ortega, Mauricio and Simmons, Jesse and Kapuria, Subir and Sharma, Amit and Jasper, Heinrich and Kapahi, Pankaj, Dietary Restriction Improves Intestinal Cellular Fitness to Enhance Gut Barrier Function and Lifespan in D. Melanogaster (2018). Available at SSRN:

    https://ssrn.com/abstract=3155743 or http://dx.doi.org/10.2139/ssrn.3155743

  • Eating a healthy diet, regular exercise (at least 30 minutes or more per day of moderate to vigorous exercise), maintaining a healthy body weight, not drinking too much alcohol (up to about one 5-ounce glass of wine per day for women, or up to two glasses for men), and not smoking during adulthood may add more than a decade to life expectancy.

    There was also a dose-response relationship between each individual healthy lifestyle behavior and a reduced risk of early death and the combination of all five healthy behaviors was linked with the most additional years of life.

    Women who maintained all five of these healthy habits gained, on average, 14 years of life, and men gained 12 years, compared with those who didn’t maintain healthy habits over the 30-year study period.

    Those individuals that maintained the healthiest lifestyles were 82% less likely to die from cardiovascular disease and 65% less likely to die from cancer compared with those with the least healthy lifestyles.

  • Reaction time and mood were improved in young individuals that consumed blackcurrant berry drink with 500 mg of polyphenols compared to placebo in a small pilot randomized controlled trial. EEG data also showed the blackcurrant drink changed brainwave activity.

    This was a small trial with a crossover study design, which means each person serves as their own control. Both the blackcurrant drink and the placebo drink had 6.98 g of sugar (glucose +fructose). They also both had the same amount of vitamin C…the only difference was that the placebo drink lacked the 500 mg of polyphenols.

    Conclusions cannot be made from this trial alone since it was a small pilot trial. However, there is a growing body of clinical trials showing polyphenols positively affect brain function in both young and old individuals.

    I understand that it would not be possible to make a placebo drink if the whole fruit was used…but I think it is better to consume the berries with the fiber which changes the way sugar is metabolized and also has benefits for the gut microbiome.

    More reading: https://www.ncbi.nlm.nih.gov/pubmed/26690214?dopt=Abstract

  • Stem cell therapy is a type of cell therapy where stem cells are introduced into the damaged tissue to treat the disorder or the injury. Mesenchymal stem cells (MSCs) are used in most stem cell therapy. They’re non-hematopoietic cell precursors initially found in the bone marrow, but actually present in many other tissues. Mesenchymal stem cells (MSCs) in culture are adherent, proliferating, and capable of multilineage differentiation into several tissues of mesenchymal origin, such as bone marrow stroma, adipose tissue (body fat), bone, cartilage, tendon, skeletal muscle and etc.

    So Why is Stem Cells Therapy Good for Anti Aging?

    In short, stem cells therapy was heavily emphasised to have the capacity to repair, renew and replace damaged tissue is a good anti aging treatment.

    As shown below are the functions of Mesenchymal stem cells (MSCs) therapy: - Help facilitate growth of new blood vessels, a process known as angiogenesis which leads to improved blood flow in tissue - An anti-inflammatory effect which fastens wound healing - After aiding wound healing, it helps in reducing size of scarred tissue such as infected cardiomyocytes (heart cells) or wound to joint injury - Repair of damaged tissue which then leads to renewal of healthy tissue - Relief if symptoms related to any chronic diseases - Vast improvement in the immune system against disease - Better digestion and elimination of constipation - More flexible joints and discs - Improvement in skin elasticity and thickness - Reducing facial pigmentation, and adding a glow to your skin - Diminishing fine lines and wrinkles - Improving skin complexion - Tightening and shrinking open pores - Removing dark circles


    No more joints problems, no more constipation, better appearance, overall human health improves!

    The list is non-exhaustive when it comes to stem cells therapy. All these benefits brought by stem cells therapy are exactly the definition of anti aging if not reviving old age.

    Visit more information on: http://stemfinitycord.co/

  • The study found that the timing of food intake relative to melatonin onset, a marker of a person’s biological night, is associated with higher percent body fat. Individuals with high body fat percentages consumed most of their calories shortly before going to sleep when melatonin levels were high, compared to individuals with lower percentages of body fat.

    To learn more about the benefits of time-restricted eating and how to practice it check out my podcasts with Dr. Satchin Panda. To learn more about how late night eating affects cancer risk check out my podcast with Dr. Ruth Patterson. Both podcasts are available on iTunes and YouTube (called foundmyfitness).

    Satchin Panda podcast: https://www.youtube.com/watch?v=-R-eqJDQ2nU Ruth Patterson podcast: https://www.youtube.com/watch?v=8qlrB84xp5g

  • A diet consisting more than 60% of energy from carbohydrates (including refined) was related to higher mortality, although not with the risk of cardiovascular disease. The research on dietary fats found that they are not associated with major cardiovascular disease, but higher fat consumption was associated with lower mortality; this was seen for all major types of fats (saturated fats, polyunsaturated fats, and monounsaturated fats), with saturated fats being associated with lower stroke risk. The data are from the Prospective Urban Rural Epidemiology (PURE) study which followed more than 135,000 people from 18 low-income, middle-income, and high-income countries. The study asked people about their diet and followed them for an average of seven and half years. The data was adjusted for age, sex, energy intake, current smoking status, urban or rural location, physical activity, baseline diabetes, education, and other dietary variables (white meat, red meat, bread, and cereal intake). However, this is a prospective study which means causation cannot be established.

  • Genetically lowering plasma insulin levels by 25% extended median lifespan by 11% in female mice fed a low-calorie/high-carb/low-fat diet and by 3% in female mice fed a high-calorie/high-fat/low-carb diet.

    This study looked at the effects of genetically lowering insulin levels in older mice. Unfortunately, the male mice did not have lower plasma levels of insulin despite genetically lowering insulin-genes and so the effect on lifespan could not be determined in male mice.

    The female mice were fed two diets: (diet A: moderate-energy diet of 4.68 kcal/g, with 20% of calories from protein, 25% from fat, and 55% from carbohydrate; diet B: high-energy diet of 5.56 kcal/g, with 16% of calories from protein, 58% from fat, and 26% from carbohydrate).

    Interestingly, the lowering of circulating insulin through gene manipulation had a more profound effect on median lifespan in female mice fed the low-calorie/high-carb/low-fat diet (11% extension) versus the high-calorie/low-carb/high-fat diet (3% extension). It is important to note that diets A and B were not matched for the type of fat content, protein levels, or micronutrient composition, so there are numerous potential factors that could have impacted diet-dependent outcomes.

  • This is an interesting rodent study. The problem is, however, broccoli sprouts are not usually advisable for women that are pregnant because they can be a source of foodborne illness. If proven safe, however, it seems (at the surface) plausible that there could be ways to reduce the risk of in the future. Perhaps through supplementation?

    FTA:

    Methods: Pregnant Long-Evans rats were administered i.p. Injections of saline (100 μl) or lipopolysaccharide (LPS, 200 μg/kg), every 12 h on embryonic day (E) 19 and 20. In the treatment groups, dams were supplemented with 200 mg/day of dried BrSp from E14 until postnatal day 21. Pups underwent a series of neurodevelopmental reflex tests from postnatal day 3–21 followed by neuropathological analyses.

    Note: LPS elicits a strong immune response.

    Results: Pups born from the LPS group were significantly growth restricted (p < 0.001) and delayed in hindlimb placing (p < 0.05), cliff avoidance (p < 0.05), and gait (p < 0.001) compared to controls. […] Dietary supplementation with [broccoli sprouts] to offspring exposed to LPS had increased birth weights (p < 0.001), were no longer delayed in acquiring hindlimb placing, cliff avoidance, gait, and posture, and groomed less compared to LPS alone pups (p < 0.01). Histological analyses revealed that LPS pups had reduced myelin basic protein compared to controls.

    The discussion had some interesting things to say about why mitigating the fetal inflammatory response is a big deal:

    An important recognized antepartum risk factor is the systemic fetal inflammatory response (FIR) [3], which is associated with a four-fold increase in the risk of developing [cerebral palsy]. Both clinical and experimental studies have provided strong evidence supporting the association between FIR and brain injury leading to [cerebral palsy].

  • Broccoli sprout extract reduced HbA1c by 7.04% in obese patients with dysregulated type 2 diabetes. It has been demonstrated that a 1% decrease of HbA1c corresponds to 37% reduced risk of microvascular complications.

    Sulforaphane reduces glucose by suppressing liver enzymes that otherwise stimulate the production of glucose.

    In animals, sulforaphane also attenuated exaggerated glucose production and glucose intolerance by a magnitude similar to that of metformin.

    Further investigations showed that while both metformin and sulphoraphane cut blood glucose, they do it in different ways. Metformin makes cells more sensitive to insulin, so they sponge more surplus glucose out of the bloodstream. Sulphoraphane reduces glucose by suppressing liver enzymes that otherwise stimulate the production of glucose. For this reason, Rosengren thinks the broccoli extract is complementary to metformin, not competitive."

  • Consuming more than one low-fat but not high-fat dairy product per day was associated with a 35-40% increased risk of developing Parkinson’s disease compared to those that had less than one serving of low-fat dairy.

    The overall risk of developing Parkinson’s disease was still quite low. Out of the 5,830 trial participants that consumed low-fat dairy only 1% of developed Parkinson’s. The 77,864 people who consumed less than one serving of low-fat dairy per day only 0.6% developed Parkinson’s disease.

    While this is an interesting observation (particularly since the finding was limited to low-fat dairy and not high fat), there is still much more to explore. Since this was not a controlled trial and the study did not control for other confounding factors (since it was looking at baseline characteristics) it is possible that other things associated with low-fat dairy consumption may increase Parkinson’s risk. For example, people that eat low-fat dairy products also may be more likely to consume other low-fat products, many which historically have had transfats in them. More research needs to be done before any conclusions can be made.

  • FTA:

    The research team studied 93 men with biopsy-proven prostate cancer who had elected not to undergo conventional treatment for reasons unrelated to this study. The participants were randomly divided into either a group who were asked to make comprehensive changes in diet and lifestyle or a comparison group who were not asked to do so.

    […] After one year, the researchers found that PSA levels (a protein marker for prostate cancer) decreased in men in the group who made comprehensive lifestyle changes but increased in the comparison group. There was a direct correlation between the degree of lifestyle change and the changes in PSA. Also, they found that serum from the participants inhibited prostate tumor growth in vitro by 70 percent in the lifestyle-change group but only 9 percent in the comparison group. Again, there was a direct correlation between the degree of lifestyle change and the inhibition of prostate tumor growth.

    Participants in the lifestyle-change group were placed on a vegan diet consisting primarily of fruits, vegetables, whole grains, and legumes supplemented with soy, vitamins and minerals. They participated in moderate aerobic exercise, yoga/meditation, and a weekly support group session.

  • From the article:

    BHB is a metabolite produced by the body in response to fasting, high-intensity exercise, caloric restriction, or consumption of the low-carbohydrate ketogenic diet. Dixit said it is well known that fasting and calorie restriction reduces inflammation in the body, but it was unclear how immune cells adapt to reduced availability of glucose and if they can respond to metabolites produced from fat oxidation.

    Working with mice and human immune cells, Dixit and colleagues focused on how macrophages – specialized immune cells that produce inflammation – respond when exposed to ketone bodies and whether that impacts the inflammasone complex.

    The team introduced BHB to mouse models of inflammatory diseases caused by NLP3. They found that this reduced inflammation, and that inflammation was also reduced when the mice were given a ketogenic diet, which elevates the levels of BHB in the bloodstream.

  • A few take-home points from the article:

    Rapid and Sustainable Detoxication of Airborne Pollutants by Broccoli Sprout Beverage: Results of a Randomized Clinical Trial in China. (PubMed Abstract)