Fiber
Episodes
Dr. Rhonda Patrick answers audience questions on various health, nutrition, and science topics in this Q&A session.
In this clip, Dr. Eran Elinav discusses the intestinal barrier's important role in absorbing nutrients while keeping out pathogens.
COVID-19 Q&A Part 2: Rhonda Patrick, Ph.D. answers subscriber questions in a multi-part series.
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Dr. Rhonda Patrick answers audience questions on various health, nutrition, and science topics in this Q&A session.
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In this clip, Dr. Eran Elinav discusses the intestinal barrier's important role in absorbing nutrients while keeping out pathogens.
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COVID-19 Vitamin D Nutrition Exercise Microbiome Sleep Vitamin C Omega-3 Inflammation Immune System Virus Micronutrients Vitamin E Vaccine Genetics Testosterone Estrogen Zinc Fiber AutoimmunityCOVID-19 Q&A Part 2: Rhonda Patrick, Ph.D. answers subscriber questions in a multi-part series.
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In this clip, Dr. Dominic D'Agostino describes the benefits of including fiber from diverse vegetable sources, both cooked and raw, within a ketogenic diet plan.
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In this clip, Dr. Peter Attia and Dr. Rhonda Patrick discuss how a healthy digestive tract interacts with the immune system to curb inflammation.
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Drs. Erica and Justin Sonnenburg both research the interaction between diet and the trillions of bacteria in the gut.
Topic Pages
News & Publications
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Statins are the first line of defense against high LDL cholesterol, but increasing the dose for better results often leads to more side effects. A team of researchers wanted to know whether adding a simple fiber supplement could make a standard statin dose more effective, without extra risk.
To find out, they analyzed data from three clinical trials that tested psyllium taken with a statin versus the same statin taken alone. The studies included 204 adults, mostly with high LDL cholesterol, who received treatment for 4 to 12 weeks. Statins used included simvastatin, atorvastatin, or lovastatin, at common doses. Psyllium was taken in daily amounts ranging from 7 to 15 grams.
The combination produced modest but meaningful improvements in cholesterol levels:
- Across all trials, adding psyllium led to an extra drop in LDL cholesterol compared to taking a statin alone.
- In one trial, 10 mg of simvastatin with psyllium lowered LDL by 63 mg/dL, compared to 55 mg/dL with the same statin dose without psyllium. That matched the effect of doubling the simvastatin dose.
- Another study showed a 31% drop in LDL with atorvastatin plus psyllium, versus a 23% drop with the statin alone.
- Psyllium alone had little effect in healthy participants with normal cholesterol, but showed a small additive benefit when taken with lovastatin.
- Side effects were fewer in the combination group than in the statin-alone group, and mostly involved mild digestive symptoms.
Why does psyllium help? The body uses cholesterol to make bile acids, which are released into the gut to help digest fat. Normally, the body recycles most of these bile acids. But psyllium forms a gel in the intestine that traps some of them in the digestive tract, so they get excreted instead. To replace them, the body pulls more cholesterol out of the bloodstream. Meanwhile, statins reduce the amount of cholesterol the liver makes. Taken together, they cut cholesterol from both directions: less is made by the liver, and more is removed from the body.
This strategy could help people who cannot tolerate higher doses of statins or want to improve their cholesterol with fewer side effects. Still, the available studies were small and short-term, and none measured whether this combination reduces heart attacks or strokes. Delve into the complexities of cholesterol in Episode #12 featuring Dr. Ronald Krauss, and explore more strategies for improving cholesterol levels in Aliquot #109.
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Infrequent bowel movements may increase the risk of kidney dysfunction. www.sciencedaily.com
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.
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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.
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Increased dietary fiber intake can help maintain muscle mass in older adults, potentially offering protection against age-related muscle loss. pubmed.ncbi.nlm.nih.gov
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.
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Inadequate maternal fiber intake during pregnancy linked to 50 percent higher risk of developmental delays in children. neurosciencenews.com
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.
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Dietary fiber may protect against severe headaches or migraines. pubmed.ncbi.nlm.nih.gov
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.
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Prebiotic supplements can compensate for low fiber intake.
Dietary fiber refers to the indigestible components of plant-based foods. A growing body of evidence indicates that eating a fiber-rich diet decreases the risks of many chronic diseases, such as coronary heart disease, stroke, hypertension, diabetes, and some types of cancer, including breast cancer and colon cancer. Most people living in the United States only get about half of the recommended amounts of fiber daily. Findings from a recent study suggest that prebiotic supplements can compensate for dietary shortcomings in fiber intake by promoting short-chain fatty acid production.
Prebiotics are food components that support the maintenance of a healthy microbiota and create an environment that is conducive to its survival. Fructo-oligosaccharides, galacto-oligosaccharides, and trans-galacto-oligosaccharides are the most common prebiotics. Their fermentation by gut microbiota produces short-chain fatty acids, including acetate, propionate, and butyrate. Many commonly consumed fruits and vegetables, such as apples, bananas, and legumes, contain prebiotics, but they are also available in dietary supplement form.
The study involved 28 healthy adults between the ages of 18 and 70 years. Each participant took one of three prebiotic supplements (inulin, wheat dextrin, or galactooligosaccharides) twice daily for one week, followed by one week off. They repeated this process with all three of the supplement products. Participants provided stool samples, completed diet surveys, and answered online surveys about their experiences with the supplements. The investigators measured short-chain fatty acid concentrations and microbial makeup in the stool samples.
They found that changes in short-chain fatty acid concentrations were person-specific and not related to which prebiotic supplement they took. Consequently, each participant’s response to the prebiotics was inversely related to their basal short-chain fatty acid concentration, which, in turn, was associated with their habitual fiber intake. Participants whose diets were low in dietary fiber experienced marked increases in butyrate production in their guts, likely due to increases in butyrate-producing microbes. However, participants whose diets were in high in dietary fiber experienced little change in the makeup of their gut microbes.
These findings suggest that people whose diets are low in dietary fiber would benefit from supplemental prebiotics to promote short-chain fatty acid production and promote gut and overall health. Learn more about prebiotics in this episode featuring Dr. Eran Elinav.
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Association Between Dietary Fiber Intake and All-Cause and Cardiovascular Mortality in Middle Aged and Elderly Adults With Chronic Kidney Disease www.ncbi.nlm.nih.gov
High dietary fiber intake reduces the risk of premature death among people with chronic kidney disease.
Chronic kidney disease, an umbrella term for a variety of conditions that impair kidney function, affects as many as 700 million people worldwide. The primary causes of chronic kidney disease are diabetes and hypertension32977-0/fulltext). Findings from a recent study suggest that high dietary fiber intake reduces the risk of premature death among people with chronic kidney disease.
Dietary fiber refers to the indigestible components of plant-based foods. A growing body of evidence indicates that eating a fiber-rich diet decreases the risks of many chronic diseases, such as coronary heart disease, stroke, hypertension, diabetes, and some types of cancer, including breast cancer and colon cancer. Public health recommendations for fiber intake vary based on a person’s age and sex. For example, adult females need between 22 and 28 grams of fiber per day, and adult males 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 study involved nearly 3,900 adults (average age, 63 years) who had chronic kidney disease and were enrolled in the Korean Genome and Epidemiology Study. The investigators collected information regarding the participants' diets (including fiber intake), lifestyle habits (such as smoking or exercising), alcohol intake, and overall health. They tracked the participants for about ten years and noted whether the participants died and, if so, their cause of death.
During the ten-year period, 602 of the participants died; of these, 149 died from cardiovascular diseases. The participants' average daily fiber intake was approximately 5 grams per day. The participants who consumed the most fiber were 37 percent less likely to die from all causes of premature death than those who consumed the least, even when considering age, sex, body mass index, smoking, exercise, hypertension, diabetes, and abnormal blood lipids. When the investigators looked at specific causes of death, they found that participants who consumed the most fiber were 44 percent less likely to die from cardiovascular diseases than those who consumed the least.
These findings suggest that dietary fiber markedly reduces the risk of premature death in people with chronic kidney disease. Interestingly, people with chronic kidney disease are often advised to reduce their intake of fiber-rich vegetables, fruits, nuts, legumes, and whole grains because these foods also contain phosphates and potassium, which carry risks in the setting of poor kidney function. However, dietary counseling regarding which foods to avoid can offset some of these risks and encourage healthy consumption of dietary fiber.
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Butyrate, a short-chain fatty acid produced in the gut, reduces skin allergies.
The skin is an important biological barrier that plays critical roles in the body’s innate immune response. Skin allergies, which typically appear early in life and can impair barrier function, have become more common in recent decades. Findings from a recent study suggest that butyrate, a short-chain fatty acid produced in the gut, reduces atopic dermatitis, a type of skin allergy.
Short-chain fatty acids are fatty acids that contain fewer than six carbons in their chemical structure. They are produced by the gut microbiota during the fermentation of dietary fiber and are crucial to gut health. Short-chain fatty acids may play roles in the prevention and treatment of metabolic syndrome, inflammatory bowel disorders, and certain types of cancer. Some evidence suggests they can cross the blood-brain barrier to affect brain function. The principal short-chain fatty acids produced in the human gut are acetate, propionate, and butyrate.
The investigators first exposed two groups of mice to an allergen that induces a skin condition similar to atopic dermatitis. They fed both groups a low-fiber diet, but they supplemented one group with inulin, a type of fiber that undergoes microbial fermentation in the gut to produce butyrate. They supplemented the other group with cellulose, which does not readily ferment. They found that compared to the cellulose-supplemented mice, the mice that ate the inulin-supplemented diet had less severe skin disease, better barrier function, and a milder immune response, which they attributed to butyrate.
Next, they tracked the movement of butyrate in the animals' bodies and determined that it traveled quickly from the gut to the skin (about 45 minutes), where it directly influenced the mitochondrial metabolism of keratinocytes, the dominant cell type in the epidermal layer of the skin. Finally, they analyzed gene expression in skin collected from both groups of mice and observed a twofold increase in gene expression related to immunity and barrier function in the butyrate-exposed mice.
These findings suggest that butyrate influences skin health and reduces skin allergies. Learn more about the beneficial health effects of butyrate in our overview article.
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For every 10-gram increase in soluble fiber eaten per day, visceral fat [but not subcutaneous] was reduced by 3.7 percent over five years www.sciencedaily.com
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.
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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.”
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Cereal fiber is associated with a lower risk of cardiovascular disease. www.sciencedaily.com
Fiber from cereal grains reduces cardiovascular disease risk.
Cardiovascular disease is the second leading cause of death worldwide. However, much of the risk associated with cardiovascular disease is modifiable via lifestyle, such as exercising, eating a healthy diet, and not smoking. Findings from a recent study suggest that eating foods rich in dietary fiber, especially the fiber present in cereal grains, reduces the risk of cardiovascular disease.
Dietary fiber is a broad term that refers to the non-digestible components of plant-based foods. It is generally characterized by its solubility in water, viscosity (i.e., ability to form thick gels), and fermentability. Cereal grains contain a mixture of insoluble fibers that bulk stool, viscous fibers that slow digestion, and fermentable fibers that feed the gut microbiota. Gut microbes break down cereal fiber, releasing micronutrients trapped in the fiber matrix and producing beneficial metabolic byproducts, such as short-chain fatty acids. Compared to fruit and vegetable fibers, cereal grain fibers tend to reduce the glycemic effect of meals and improve blood lipids, while supporting a healthy and diverse microbiota.
The investigation involved more than 4,100 participants (aged 65 years and older) enrolled in the Cardiovascular Health Study. Participants provided detailed information about their demographics, dietary intake, and medical history, including cardiovascular events. Because evidence indicates that cereal fibers reduce markers of inflammation, including C-reactive protein, the investigators measured various inflammatory markers, including CRP, IL-6, CD14, CD163, IL-2 receptor α, IL-1RA, IL-18, and TNF receptor 1, in the participants' blood.
The investigators found that higher cereal grain fiber intake markedly reduced cardiovascular disease risk and lowered the inflammatory markers CRP, IL-6, and IL-1RA. However, statistical analysis revealed that this decrease in inflammation had a modest effect on reducing cardiovascular risk, mediating just one-sixth of the association between cardiovascular disease and cereal grain fiber intake.
These findings suggest that eating foods rich in cereal grain fibers reduces the risk of cardiovascular disease and lowers inflammation. Additional studies are needed to tease out all the mechanisms that drive the protective effects of cereal fiber on cardiovascular health.
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Resistant starch may reduce colorectal cancer risk associated with red meat consumption www.sciencedaily.com
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.
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β-Hydroxybutyrate may be a substitute for butyrate in protecting from colon cancer: BHB activates a natural receptor involved in killing cancer cells www.sciencedaily.com
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.
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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.
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Fiber-rich diets may reduce the risk of all causes of premature death. Fiber-rich diets may reduce the risk of all causes of premature death.
Dietary fiber refers to the indigestible components of plant-based foods. A growing body of evidence indicates that eating a fiber-rich diet decreases the risks of many chronic diseases, such as coronary heart disease, stroke, hypertension, diabetes, and some types of cancer, including breast cancer and colon cancer. Findings presented in a 2015 report suggest that fiber-rich diets reduce the risk of all causes of premature death.
Public health recommendations for fiber intake vary based on a person’s age and sex. For example, females need between 22 and 28 grams of fiber per day, and males 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 authors of the report analyzed the data from 17 studies investigating links between dietary fiber intake and the risk of premature death. The studies involved more than 980,000 healthy adults and spanned a period of 20 years. The authors categorized the participants by age, sex, study population and location, dietary assessment method, and follow-up period. They also took various risk factors among the participants into account, such as their body mass index, physical activity level, cholesterol levels, blood pressure, and whether they smoke or drank alcohol.
The analysis revealed that more than 67,000 of the various study participants died during the study period. Among the people that died, those with the highest dietary fiber intake were 16 percent less likely to die from premature causes when compared to those with the lowest intake. For every 10-gram increase of fiber intake per day, the risk of premature death decreased 10 percent.
These findings suggest that dietary fiber exerts a robust protective effect against premature death. Public health efforts aimed at increasing dietary fiber intake may be beneficial for reducing all causes of premature death.
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Dietary fiber helps maintain muscle mass. onlinelibrary.wiley.com
Muscle mass decreases markedly with aging, compromising overall fitness and contributing to frailty, disability, and falls. Findings from a recent study suggest that dietary fiber helps reduce muscle mass losses associated with aging.
Dietary fiber refers to the indigestible components of plant-based foods. It is classified as either soluble or insoluble. Soluble fiber, which is found in grains, nuts, seeds, legumes, and some vegetables and fruits, dissolves in water and may reduce blood glucose and cholesterol levels. Insoluble fiber, which is found in wheat bran, vegetables, and whole grains, does not dissolve in water. It promotes digestive health. Processed foods are typically low in fiber.
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 authors of the study drew on data collected over a seven-year period via the National Health and Nutrition Examination Survey. Study participants, which included more than 5,000 adults aged 40 years and older, provided information about their dietary intake and underwent physical exams (including the collection of blood and urine samples) to assess body composition, grip strength (a predictor of functional impairment and premature death), and metabolic health.
They found that people whose diets were rich in dietary fiber had greater lean body mass, bone mineral content, and grip strength compared to those with low intake. People whose diets were rich in dietary fiber were also more likely to have lower body mass index, body fat, fasting glucose, fasting insulin, and HOMA-IR (a measure of insulin resistance) than those with low intake.
These findings suggest that higher dietary fiber intake helps maintain muscle mass in older adults. Evidence indicates that sauna use improves muscle and bone mass, as well. Learn more about the health benefits of sauna use in this article by Dr. Rhonda Patrick.
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Disruption of the gut microbiome and gut barrier may be the primary cause of age-related inflammation which accelerates the aging process. www.sciencedaily.com
This study showed that older mice have imbalances in the bacterial composition in the gut which then leads to the breakdown of the gut barrier and the release of bacterial products that trigger inflammation and impair immune function.
We know that inflammation has recently been identified as the key driver of aging in 4 different age groups including elderly, centenarians, semi-supercentenarians, and supercentenarians. We also know that lack of fermentable fiber starves the gut microbiome and causes the bacteria to eat the gut barrier which is made of carbohydrates and this results in the breakdown of the barrier and inflammation.
For more information on why fermentable fiber is so important for the gut microbiome and what good sources are…listen to my podcast with gut experts, Drs. Justin and Erica Sonnenburg. YouTube: https://youtu.be/gOZcbNw7sng
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Clinical trial shows whole grains modestly increase good gut bacteria, lower inflammatory gut bacteria, improve immune cells. www.sciencedaily.com
New clinical trial shows that people that were given whole grains had a modest improvement in a good type of gut bacteria, modestly lowered inflammatory gut bacteria, and modestly increased memory T cells after 6 weeks compared to those given refined grains. Since this study compared gut bacteria, inflammatory biomarkers, and immune cells in people given whole grains versus refined grains it is difficult to draw any conclusions about whole grains compared to no grains. However, there have been other intervention trials that have shown whole grains lowered inflammatory biomarkers possibly through their effect on the microbiome. Also, this intervention trial was only 6 weeks which may also account for the modest effect on the microbiome. Things are probably much more complicated and have a lot to do with gene polymorphisms (which affect an individual’s glucose response), gut health, gluten sensitivity, and other factors. I do not think any absolute conclusions can be drawn from this study but still interesting to think about.