Visceral Fat
Episodes
Dr. Valter Longo discusses how the fasting-mimicking diet is one of the few dietary interventions that can increase relative lean body mass.
Dr. Valter Longo describes how a fasting-mimicking diet can be used for fat loss while preserving lean muscle mass.
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Dr. Valter Longo discusses how the fasting-mimicking diet is one of the few dietary interventions that can increase relative lean body mass.
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Prolonged fasting and fasting-mimicking preferentially deplete visceral fat rather than lean mass ClipDr. Valter Longo describes how a fasting-mimicking diet can be used for fat loss while preserving lean muscle mass.
Topic Pages
News & Publications
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Eating a polyphenol-rich diet may cut abdominal fat. bmcmedicine.biomedcentral.com
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.
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Postmenopausal women may have lower postprandial fatty acid oxidation, greater meal fatty acid storage, and direct free fatty acid storage. (2013) www.sciencedaily.com
From the article:
Santosa’s research compared fat storage in pre- and post-menopausal women. The 23 women who participated in the study were in the same age range, and had similar Body Mass Indices and body fat composition. These similarities allowed Santosa to isolate the effects of estrogen on fat absorption and storage.
She and Jensen were able to examine the activity of certain enzymes and proteins that regulate fat storage in post-menopausal women’s abdomens and thighs. By considering these factors together rather than in isolation, the researchers determined conclusively that the overall fat storage “machinery” is more active in post-menopausal women. In other words, these cells now store more fat than they did before menopause.
In addition, post-menopausal women burned less fat than their pre-menopausal colleagues. These changes mean that their cells are not only storing more fat, but are also less willing to part with it. This combination is a recipe for rapid weight gain. “Taken together, these changes in bodily processes may be more than a little surprising – and upsetting – for women who previously had little trouble managing their weight,” comments Santosa.
Though the increased cellular activity revealed by this study was not specific to the abdominal region, more fat stored overall means more abdominal fat.
From the publication:
We found that meal FA [fatty acid] storage in subcutaneous fat was greater in postmenopausal than in premenopausal women. This difference was especially evident in the femoral depot, where meal FA [fatty acid] storage in postmenopausal women was double that of premenopausal women.
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The increase in fat storage stems from somewhat greater LPL [lipoprotein lipase] activity and significantly greater content of adipocyte FA [fatty acid] storage factors. It is possible that the upregulation in proteins associated with FA [fatty acid] storage capacity in postmenopausal women contributes to the decrease in postprandial total fat oxidation. Whether the differences in FA [fatty acid] storage between premenopausal and postmenopausal women are attributable to the effects of estrogen or the combination of estrogen, progesterone, and other factors, such as changing insulin concentrations, remains to be elucidated.
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Estrogen may reduce high-fat diet-induced visceral fat accumulation by decreasing the expression of a vitamin A-converting enzyme - mouse study.(2012) www.sciencedaily.com
From the article:
The hormonal effect seen in these mice relates at least in part to how the female body processes vitamin A, a nutrient that is converted into a variety of compounds. These include a molecule that supports the burning of fat for energy, as well as retinoic acid, the hormone in this study that leads to the formation of visceral fat. The scientists showed that a high-fat diet functions as a switching mechanism that breaks down the fat-burning molecule and leads to activation of the enzyme and production of retinoic acid, ending in the development of visceral fat.
A year ago, Ziouzenkova’s lab identified the one of these enzymes that relates to fat accumulation: Aldehyde Dehydrogenase 1, or Aldh1a1. In the current study, she and colleagues conducted numerous experiments in mice to track the events that followed activation of this enzyme.
The researchers compared normal mice with genetically altered mice lacking the enzyme over almost a year of eating a high-fat diet. Male and female normal mice gained weight on the high-fat diet, as expected, though the females developed more visceral fat that surrounds the organs than did males, a trend also seen in humans as the result of eating excess fat. (In contrast, on a regular diet, men are more likely than women to form abdominal fat.) Both sexes of mice developed peripheral subcutaneous fat, which lies just under the skin and has some benefits.
In mice without the enzyme, however, the males developed some fat but females remained lean, and this occurred even when females ate more food than males. The researchers determined that without Aldh1a1, the females were not producing retinoic acid, and that protected them from producing visceral fat. Meanwhile, males retained the ability to produce retinoic acid.
The scientists then analyzed the proteins contained in fat tissue in male and female mice lacking the enzyme, and saw that only the females' fat cells contained high levels of a protein that releases fat from fat cells to support fat burning. This release led to production of another protein that converts fat to heat, essentially burning the fat, in the form of lipids, away.
“Without production of the hormone retinoic acid, females are burning fat and expending the energy in the form of heat. That’s why they stay very lean,” Ziouzenkova said. “And this process was specifically affecting visceral fat.”
The researchers surgically removed the ovaries of mice to test whether estrogen could be related to visceral fat production in females. As soon as the animals became menopausal and weren’t producing estrogen, they began to produce retinoic acid, which led to visceral fat formation.
“Estrogen was sufficient to protect female mice from both hormonal and, partially, diet-induced obesity. This means estrogen is suppressing activation of the obesity-inducing hormone, and as soon as we lose this estrogen during menopause, the visceral fat starts to grow,” said Ziouzenkova, also an investigator in Ohio State’s Comprehensive Cancer Center.
Using another mouse model that allowed researchers to measure hormone production specifically, the researchers observed that female mice on a regular diet barely produced retinoic acid. However, females on a high-fat diet produced high levels of the hormone and, in turn, showed a nine-fold increase in visceral fat compared to visceral fat developed by males on a high-fat diet. This was the final determinant that the high-fat diet triggers this cascade of events ending in visceral fat formation.
Because the human fat tissue samples the researchers analyzed also showed elevated levels of Aldh1a1 in cells extracted from tissue in obese women, “it could be that what we show about this hormone’s importance to visceral obesity in mice is also true for humans,” Ziouzenkova said.
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Silencing of estrogen receptor α in a brain area of the hypothalamus led to metabolic syndrome in mice. (2007) www.sciencedaily.com
From the article:
Estrogen receptors are located on cells throughout a woman’s body. Previous studies have shown that one type of estrogen receptor, known as estrogen receptor alpha or ER-alpha, plays a role in regulating food intake and energy expenditure. But scientists have been unable to pinpoint exactly where these fat-regulating receptors reside or how they work to govern these behaviors.
To determine the effect of dwindling estrogen levels in the brain, Clegg and her colleagues are focusing on two ER-alpha rich regions located in the hypothalamus, an area of the brain that controls body temperature, hunger and thirst. The first region, called the ventromedial nucleus or VMN, is a key center for energy regulation.
Using a relatively new gene-silencing technique called RNA interference, the researchers in earlier research deactivated the alpha-receptors in the VMN. The estrogen receptors in other regions of the brain maintained their normal capacity.
When estrogen levels in the VMN dipped, the animals' metabolic rate and energy levels also plummeted. The findings show the animals quickly developed an impaired tolerance to glucose and a sizable weight gain, even when their caloric intake remained the same. What’s more, the excess weight went straight to their middle sections, creating an increase in visceral fat.
The findings suggested that the ER-alpha in this region plays an essential role in controlling energy balance, body fat distribution and normal body weight.
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Estradiol administered to the amygdala of a menopause rat model prevented weight and abdominal fat gain and improved glucose tolerance. (2017) www.sciencedaily.com
From the article:
“We know as women age and enter into menopause, they tend to gain body weight and body fat, particularly in the abdominal or ‘belly’ area. Excess abdominal fat greatly increases risk for cardio-metabolic diseases,” says Solomon. “While there are likely many factors that are associated with these risks in menopausal women, estrogen loss is associated with body weight and fat gain during menopause. In fact, estrogen treatment can offset this weight gain in many women.”
The medial amygdala (MeA) is a region of the brain that helps regulate body weight and contains an abundance of estrogen receptors (molecules that respond to estrogen). The researchers used an experimental model in rats, which involves removing the ovaries to mimic the hormonal changes of menopause. They targeted estrogen replacement directly in the MeA and found that it prevented weight and abdominal fat gain and improved glucose tolerance, compared to rats in a placebo group. This suggests that the MeA is important in the metabolic health of menopausal females and may be a useful target for treatment.
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Estrogen mitigates the association between visceral fat on cognitive decline.
Estradiol, a form of estrogen, is the primary female sex hormone. It participates in menstrual cycle regulation and drives the development of female secondary sex characteristics, such as breasts, a wider pelvis, and gynoid fat – fat that forms around the hips, thighs, and breasts. Evidence suggests that estradiol exerts both cardioprotective and neuroprotective effects. Findings from a 2020 study demonstrate that estradiol mitigates the association between visceral fat on cognitive decline.
Cognitive decline is characterized by altered brain structural networks and accelerated degeneration with aging. Scientists don’t fully understand the biological mechanisms that drive cognitive decline, but evidence indicates that visceral fat – a type of fat that accumulates in the abdominal cavity – may play a role. Visceral fat is metabolically active and is associated with increased markers of inflammation and oxidative stress, and decreased levels of anti-inflammatory proteins, such as adiponectin
The cross-sectional study involved 974 cognitively healthy females and males (average age, ~50 years). Using magnetic resonance imaging, the investigators measured the participants' gray matter volume, cerebral cortex area, intracranial blood vessels, and visceral fat. They also measured estradiol concentrations in a subset (390) of the females. All the participants completed neuropsychological testing to assess memory performance.
The investigators found that visceral fat exacerbated the harmful effects of aging on the brain’s structural networks in both females and males. However, estradiol mitigated some of these effects in the females, but not the males. Females between the ages of 35 and 55 years (the period surrounding menopause) who had lower estradiol concentrations were more likely to exhibit greater structural network impairments and worse memory performance.
These findings suggest that estradiol mitigates some of the harmful effects of visceral fat on the brain’s structural networks and cognitive health. Interestingly, the fasting-mimicking diet preferentially depletes visceral fat. Learn more in this clip featuring Dr. Valter Longo.
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Strict 12-week keto without calorie counting: participants lost >5% percent body fat, 44% of their visceral fat, and 48% better insulin sensitivity www.sciencedaily.com
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.
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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.
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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).
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Cold treatment and sympathetic nervous stimulation increases T Regulatory cells (Tregs) in fat tissue: brown fat most of all, visceral least www.sciencedaily.com
From the article:
The number of obese people as well as those suffering from type 2 diabetes is increasing worldwide. Both disorders are associated with metabolic changes including amplified inflammatory responses in adipose tissue. “Previous studies have indicated that immunosuppressive regulatory T-cells – or Tregs for short – play an important role in these processes,”[…]
[They] determined that the number of Tregs in adipose tissue increases in response to different environmental stimuli. These stimuli included a short-term cold treatment, stimulation of the sympathetic nervous system (beta-3-adrenoreceptors) or short-term high-caloric exposure. “All these stimuli supported those immunosuppressive cells directly in the adipose tissue,”
T regulatory cell response to cold and adrenaline reduced in visceral fat:
The magnitude of the increase in Tregs differed depending on the type of adipose tissue: it was particularly pronounced in brown fat, somewhat weaker in subcutaneous fat and weakest in visceral fat.
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Visceral fat and total brain volume inversely linked independent of BMI and insulin resistance: a relationship between dementia and obesity www.sciencedaily.com
From the article:
Preliminary findings suggest a relationship between obesity and dementia that could lead to promising prevention strategies in the future.
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“Our results confirm the inverse association of increasing BMI with lower brain volumes in older adults and with younger, middle-aged adults and extends the findings to a much larger study sample,” […] “More importantly our data suggests a stronger connection between central obesity, particularly the visceral fat component of abdominal obesity, and risk of dementia and Alzheimer’s disease,” Dr. Seshadri added. The research showed the association between visceral adipose tissue and total brain volume was most robust and was also independent of BMI and insulin resistance."
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PCB exposure linked to increased visceral fat: "persistent compound PCB189 was related to a high proportion of fat in the abdomen" www.sciencedaily.com
Exposure to PCBs may increase visceral fat.
Persistent organic pollutants are ubiquitous environmental toxicants that pose considerable threats to human health. These compounds typically degrade slowly and are often referred to as “forever compounds.” A 2012 study found that exposure to the organic pollutants polychlorinated biphenyls (PCBs) was associated with having increased visceral fat.
PCBs were historically used in industrial and chemical applications, such as coolants, transformer insulators, capacitors, motors, paints, and electrical wire coatings. Although PCBs have been banned in the United States, the compounds are widespread in the environment. Exposure to PCBs is associated with an increased risk of adverse health effects, including many chronic disorders, such as cardiovascular disease, diabetes, hypertension, melanoma, and non-Hodgkin’s lymphoma. PCB exposure may also be linked to neurodegenerative disease PCBs bioaccumulate in human muscle and adipose tissue, brain, liver, and lungs and have long elimination half-lives, ranging from 10 to 15 years.
The cross-sectional study involved more than 1,000 adults (70 years and older) living in Sweden. Participants provided information about their medical histories, education level, exercise habits, smoking habits, and medication use. A subset of 287 participants underwent magnetic resonance imaging to assess body fat location and quantity. Investigators collected blood samples from the participants to detect the presence of persistent organic pollutants.
They found that higher blood concentrations of the organic pollutant PCB189, a highly chlorinated PCB, were associated with having greater quantities of visceral fat, suggesting that environmental exposures influence fat deposition in humans. Interestingly, PCB189 exposure and increased visceral fat are associated with type 2 diabetes, potentially providing a mechanistic link between body fat and diabetes risk.
Although exposure to persistent organic pollutants is likely unavoidable, some PCBs are excreted in sweat. Sauna use, which induces copious sweating, may promote PCB excretion. Learn more about the beneficial health effects of sauna use in our overview article.
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Visceral fat may be less circadian than (healthier) subcutaneous fat: only subcutaneous showed circadian rhythmicity in insulin sensitivity www.sciencedaily.com
From the article:
Using samples of adipose tissue from both visceral fat and subcutaneous fat from 18 people who underwent gastric bypass surgery, researchers found that subcutaneous fat has an intrinsic circadian rhythm in insulin sensitivity. Insulin sensitivity reached its maximum around noon, and was more than 50 percent higher than at midnight. Interestingly, the rhythm was not observed in visceral fat.
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“Our study demonstrates that subcutaneous human fat tissue has an internal clock that is able to regulate insulin sensitivity even when outside of the body. This tissue rhythm matches well with what has been observed in humans overall when examining how people cope with a meal or sugar load,”
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Visceral fat intimately linked with the hypertensive effect of obesity: "only abdominal fat remained independently associated with hypertension" www.sciencedaily.com
From the article:
For this study, 903 patients enrolled in the Dallas Heart Study were followed for an average of seven years to track development of hypertension. […] Patients also received imaging of visceral fat, or fat located deep in the abdominal cavity between the organs; subcutaneous fat, or visible fat located all over the body; and lower-body fat.
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At the end of the study period, 25 percent of patients developed hypertension. While higher BMI was associated with increased incidence of hypertension, when abdominal fat content, overall fat content and lower-body fat content were factored in, only abdominal fat remained independently associated with hypertension.
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Retinol-binding protein 4 (RBP4) may be a biomarker for visceral fat accumulation: levels of RBP4 double or triple in concentration compared to normal www.sciencedaily.com
From the article:
The researchers, including Barbara Kahn and Timothy Graham of Harvard Medical School and Matthias Blüher of the University of Leipzig in Germany, showed that “retinol-binding protein 4” (RBP4) is produced in much greater amounts by visceral fat compared to the subcutaneous fat that lies just beneath the skin. Moreover, they report that blood serum levels of RBP4 jump in people who are obese, who have double or even triple the concentrations found in individuals of normal weight.
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The only known function of RBP4 was to carry vitamin A (also known as retinol) in the blood, Kahn said.
Large gene expression changes in visceral fat:
n a study of 196 people, the researchers now reveal that RBP4 is indeed preferentially produced in the deep fat that covers organs of the belly. RBP4 gene expression activity levels spiked about 60-fold in the visceral fat of viscerally obese relative to lean study participants, they found. By comparison, visceral fat RBP4 concentrations were increased just 12-fold in obese individuals with a preponderance of subcutaneous fat.
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Removing the visceral fat in female mice reduces intestinal tumors and extends survival (a sex-specific effect) www.sciencedaily.com
From the article:
“There has been some skepticism as to whether obesity per se is a bona fide cancer risk factor, rather than the habits that fuel it, including a poor diet and a sedentary lifestyle,” […] “Although those other lifestyle choices play a role, this study unequivocally demonstrates that visceral adiposity is causally linked to intestinal cancer.”
There was a sex-specific effect:
The researchers then subdivided the groups by gender. In female mice, the removal of visceral fat was significantly related to a reduction in intestinal tumors, but calorie restriction was not. In male mice, calorie restriction had a significant effect on intestinal tumors, but removal of visceral fat did not.
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Greater visceral and total body fat associated with vascular brain injury and impaired cognitive scores www.sciencedaily.com
From the article:
In the study, 9,166 participants were measured by bioelectrical impedance analysis to assess their total body fat.
As well, 6,733 of the participants underwent magnetic resonance imaging (MRI) to measure abdominal fat packed around the organs known as visceral fat, and the MRI also assessed vascular brain injury – areas in the brain affected by reduced blood flow to the brain.
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Co-author Eric Smith, a neurologist, scientist and an associate professor of clinical neurosciences at the University of Calgary, said that “preserving cognitive function is one of the best ways to prevent dementia in old age. This study suggests that one of the ways that good nutrition and physical activity prevent dementia may be by maintaining healthy weight and body fat percentage.”
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Plasmacytoid dendritic cells (pDCs) are a special immune cell that accumulate in visceral fat, producing lymphoid structures driving secondary disease www.sciencedaily.com
An obesogenic diet drives immune cell activation.
Although the role of dietary fat intake in obesity is a matter of considerable controversy, research has identified complex interrelationships between dietary components, inflammation, and immune function. For example, some evidence suggests that consumption of a diet high in fat drives inflammatory processes in the central nervous system and peripheral tissues, including the liver, adipose tissue, skeletal muscle, and gut, promoting metabolic dysfunction and weight gain. Findings from a recent study suggest that a high-fat diet promotes the activity of plasmacytoid dendritic cells, a type of immune cell.
Plasmacytoid dendritic cells, also known as natural interferon-producing cells, are critical components of both the innate and adaptive immune response. These specialized cells secrete copious amounts of type 1 interferons in response to a viral infection and then differentiate into professional antigen-presenting cells, which can stimulate T cell activity. Chronic stimulation of the plasmacytoid dendritic cells is linked with the development of autoimmune disorders and certain types of cancer. Although plasmacytoid dendritic cells are somewhat rare, they have been identified in visceral adipose tissue.
The investigators fed multiple groups of mice either a high-fat diet or standard chow for three weeks. They gave one group of mice on the high-fat diet a drug that blocks the migration of plasmacytoid dendritic cells into the visceral adipose tissue. Then they analyzed the animals’ blood, peripheral tissue, lymphatic organs, and visceral adipose tissue for the presence of plasmacytoid dendritic cells.
They found that after three weeks of a high-fat diet, plasmacytoid dendritic cells increased in the blood, liver, spleen, and visceral adipose tissue. The cells were especially abundant in fat-associated lymphoid clusters within the visceral adipose tissue. The animals on the high-fat diet gained weight and exhibited poor glucose tolerance, indicating metabolic dysfunction. Their visceral adipose tissue weight doubled during the three-week diet. Animals that received the drug that blocked plasmacytoid dendritic cell migration did not gain weight and demonstrated better glucose tolerance.
These findings suggest that an obesogenic diet drives visceral and peripheral weight gain, promotes glucose intolerance, and increases immune cell activation in the visceral adipose tissue of mice.
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Longer periods of lactation (breast feeding) may promote lower visceral and pericardial fat, an effect that persists many years through midlife www.sciencedaily.com
Breastfeeding may reduce fatty deposits around the heart and other organs.
The benefits of breastfeeding on infant health are widely known, but breastfeeding benefits maternal health, too. For example, evidence suggests that women who breastfeed experience a faster return to pre-pregnancy weight and have a lower risk of developing cardiovascular disease and certain types of cancer Findings from a 2021 study suggest that breastfeeding is associated with having less pericardial and visceral adipose tissue.
Pericardial adipose tissue is fat that accumulates in and on the pericardium – the membrane that surrounds the heart. Visceral adipose tissue is fat that is stored in the abdominal cavity near the liver, pancreas, and intestines. Evidence suggests that pericardial and visceral fat produce adipokines, cell-signaling molecules that drive metabolic dysfunction.
The investigators drew on data from the Coronary Artery Risk Development in Young Adults study, an ongoing examination of the risk factors for cardiovascular disease in young adults living in the United States. The participants included 910 women who had given birth at least once during the 25 years of follow-up. They provided information about their reproductive histories, overall health, lifestyles, and how long they breastfed. The investigators used computed tomography to measure the women’s body fat.
They found that women who breastfed had less pericardial and visceral fat than women who did not, even when considering the women’s age, race, smoking status, body mass index, fasting glucose, family history of diabetes, fat intake, total cholesterol, and physical activity. The protective effects of breastfeeding were duration-dependent, with longer-duration breastfeeding exerting greater effects, and appeared to last through midlife.
These findings suggest that breastfeeding is associated with having less pericardial and visceral adipose tissue. Learn more about the benefits of breastfeeding in our overview article.
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An unexpected way to shed visceral fat through the sebaceous gland: "We believe that we are the first group to show a non-hormonal way to induce this" www.sciencedaily.com
From the article:
Treating obese mice with the cytokine known as TSLP led to significant abdominal fat and weight loss compared to controls […] Unexpectedly, the fat loss was notassociated with decreased food intake or faster metabolism. Instead, the researchers discovered that TSLP stimulated the immune system to release lipids through the skin’s oil-producing sebaceous glands.
Thymic stromal lymphopoietin:
Thymic stromal lymphopoietin (TSLP) is a cytokine – a type of immune system protein – involved in asthma and other allergic diseases. The Kambayashi research group has been investigating the expanded role of this cytokine to activate Type 2 immune cells and expand T regulatory cells. Since past studies have indicated that these cells can regulate energy metabolism, the researchers predicted that treating overweight mice with TSLP could stimulate an immune response, which could subsequently counteract some of the harmful effects of obesity.
“When I looked at the coats of the TSLP-treated mice, I noticed that they glistened in the light. I always knew exactly which mice had been treated, because they were so much shinier than the others,” he said. Kambayashi considered a far-fetched idea – was their greasy hair a sign that the mice were “sweating” out fat from their skin?
Does this mechanism exist in humans?
To examine whether TSLP could potentially play a role in the control of oil secretion in humans, the researchers then examined TSLPand a panel of 18 sebaceous gland-associated genes in a publicly-available dataset. This revealed that TSLPexpression is significantly and positively correlated with sebaceous gland gene expression in healthy human skin.
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Visceral fat may cause pathogenic obesity reinforced through a cycle of chronic inflammation www.sciencedaily.com
Scientist proposes that the bodies decision to promote visceral fat rather than subcutaneous fat may be due to underlying biological switches triggered partly by malnutrition.
The evolutionary advantage of visceral fat:
Sometimes called “the abdominal policeman,” a VAT-rich structure called the omentum, a loosely hanging fold of the membrane lining the abdominal cavity, sticks to wounds, foreign objects such as shrapnel and infection sites like a bandage full of antibiotics. In fact, surgeons sometimes use pieces of omentum to control severe postoperative infections. VAT surrounds the small intestine, defending the body from ingested pathogens and toxins.
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In the past, the role of visceral fat as part of the immune system may have been more widely important than it is today because starvation and infections were more common. West-Eberhard proposes that in fetuses subject to nutritional stress, more energy may be stored as fat around the abdominal organs rather than as fat under the skin (subcutaneous fat or SAT).
Chronic inflammatory feedback loop promotes development of visceral fat:
In overweight individuals, a dangerous feedback loop may develop: increased VAT leads to increased chronic inflammation, which, in turn, leads to increased insulin resistance leading to further VAT storage and increased susceptibility to disease.
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Brain insulin sensitivity determines fat distribution: insulin sensitivity in the hypothalamus form little visceral, but no influence on subcutaneous www.sciencedaily.com
From the article:
If the person’s brain responds sensitively to the hormone, a significant amount of weight can be lost, unhealthy visceral fat reduced, and the weight loss can be maintained over the long term. However, If the person’s brain responds only slightly or not at all to insulin, the person only loses some weight at the beginning of the intervention and then experiences weight regain. Over the long term, the visceral fat also increases.
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Since the insulin action in the hypothalamus is crucial for the regulation of peripheral energy metabolism, the researchers also investigated how insulin sensitivity in this area of the brain is related to the distribution of body fat. For this purpose, they examined a cross-sectional cohort of 112 participants. The analysis of the data showed that people with high insulin sensitivity in the hypothalamus form little visceral fat. However, insulin sensitivity has no influence on the mass of subcutaneous fat.
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Sugar-sweetened drinks linked to increased visceral fat www.sciencedaily.com
Sugar-sweetened beverage intake increases visceral fat.
Subcutaneous fat is stored just beneath the skin. Commonly associated with a “pear” shape, subcutaneous fat may protect against some diseases. Visceral fat, on the other hand, is stored in the abdominal cavity close to internal organs such as the liver, pancreas, and intestines. An excess of visceral fat, often referred to as central obesity or abdominal obesity, is commonly associated with an “apple” shape and an increased risk of developing many chronic diseases. Findings from a 2016 study suggest that sugar-sweetened beverage intake increases visceral fat deposition.
Sugar-sweetened beverages include commonly consumed products such as soda, sports drinks, energy drinks, and other beverages that contain added sugars. Many sugar-sweetened beverages exceed the recommended maximum daily added sugar intake of 25 grams in a single serving. They are the leading contributor to sugar intake among people living in the United States.
The investigation involved 1,160 participants enrolled in the Third Generation of the Framingham Heart Study who underwent repeated computed tomography scans (approximately six years apart) to assess the amount of fat in their abdominal region, including subcutaneous fat and visceral fat. Participants provided information about their dietary intake, physical activity, overall health, and whether they smoked. Investigators categorized the participants according to their sugar-sweetened beverage or diet soda intake, ranging from non-consumers (drinking none to less than one serving per month) to daily consumers (drinking one or more servings per day.
They found that sugar-sweetened beverage intake was associated with visceral fat gain in a dose-dependent manner, with daily consumers gaining 29 percent more visceral fat over a six-year period than non-consumers. These findings held true even after accounting for the participants' age, gender, physical activity, body mass index, and other factors. Drinking diet soda was not associated with visceral fat gain.
These findings suggest that drinking sugar-sweetened beverages increases visceral fat, potentially contributing to an increased risk of chronic disease. Learn more about sugar-sweetened beverages in our overview article.
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Even low exercise groups prevents accumulation of visceral fat (vigorous sees declines): highest level saw a 6.9 percent decrease in visceral fat www.sciencedaily.com
From 2005.
From the article:
To better understand the effects of differing amounts of exercise, the researchers studied 175 overweight sedentary men and women who were beginning to show signs of lipid problems. They were randomized into one of four groups: no exercise, low dose/moderate intensity (equivalent of 12 miles of walking per week), low dose/vigorous intensity (12 miles of jogging per week) or high dose/vigorous intensity (20 miles of jogging per week).
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“On the other hand, participants who exercised at a level equivalent to 17 miles of jogging each week saw significant declines in visceral fat, subcutaneous abdominal fat and total abdominal fat,” Slentz continued. “While this may seem like a lot of exercise, our previously sedentary and overweight subjects were quite capable of doing this amount.”
Specifically, those participants exercising at the highest level saw a 6.9 percent decrease in visceral fat and a 7 percent decrease in subcutaneous fat.
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Fibroblast growth factor-2 released by visceral fat tumorigenic: "when the fat secretions had more of FGF2, more of the cells formed cancerous tumors" www.sciencedaily.com
From the article:
A new Michigan State University study now offers new details showing that a certain protein released from fat in the body can cause a non-cancerous cell to turn into a cancerous one. The federally funded research also found that a lower layer of abdominal fat, when compared to fat just under the skin, is the more likely culprit, releasing even more of this protein and encouraging tumor growth.
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“Our study suggests that body mass index, or BMI, may not be the best indicator,” Bernard said. “It’s abdominal obesity, and even more specifically, levels of a protein called fibroblast growth factor-2 that may be a better indicator of the risk of cells becoming cancerous.”
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She also collected visceral fat tissue from women undergoing hysterectomies and found that when the fat secretions had more of the FGF2 protein, more of the cells formed cancerous tumors when transferred into mice.
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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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Inadequate sleep may preferentially act as a trigger for visceral fat accumulation (randomized controlled crossover study) www.sciencedaily.com
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.
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Exercise reduces tumor growth via the actions of myokines produced in exercising muscle www.sciencedaily.com
Epidemiological data indicate that regular exercise not only reduces the risk of developing cancer, but it also improves survival among people who have been diagnosed with cancer. Two theories have emerged to explain exercise’s tumor-suppressive effects. Whereas one theory suggests that exercise acts via direct physical effects on tumor cells, the other theory suggests that it acts via indirect effects related to the tumor microenvironment. Findings from a recent study suggest that myokines suppress tumor growth.
Myokines are cell-signaling proteins produced in muscles during exercise. Evidence indicates that myokines exert direct anti-inflammatory effects on visceral fat and muscles. They also participate in metabolic pathways involving fat oxidation and glucose uptake – critical factors in tumor survival.
The intervention study involved 10 prostate cancer patients (average age, 73 years) who were undergoing androgen deprivation therapy, a common treatment for prostate cancer that often decreases muscle mass and increases fat mass. The patients engaged in a 12-week exercise program that included resistance and aerobic activities. The patients took a protein supplement that provided 40 grams of protein immediately after each exercise session to promote muscle protein synthesis. The authors of the study assessed the patients' body composition via dual-energy X-ray absorptiometry and measured their muscle strength via the one-repetition maximum method. Before and after the intervention, they measured the patients' fasting blood glucose; serum concentrations of myokines, including oncostatin M (which exibits anti-cancer effects); and prostate cell number and growth rate.
They found that at the end of the intervention, the patients' fat mass, percent body fat, and body weight had decreased, but their lean mass and strength increased. Concentrations of oncostatin M and prostate cancer cell number and growth rate decreased.
These findings suggest that exercise exerts anti-tumor effects via the actions of myokines produced in exercising muscles. They also underscore the importance of remaining physically active throughout the lifespan. Learn how exercise, in conjunction with fasting, may work synergistically to benefit health in this episode featuring Dr. Mark Mattson.
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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.
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Beige fat protects against dementia by reducing visceral-like properties of subcutaneous fat www.sciencedaily.com
The color of fat tissue – white, brown, or beige – dictates the role the tissue plays in the body. Whereas white fat is involved in lipid storage and the release of free fatty acids for energy, brown fat is involved primarily in thermogenesis – the production of heat. Beige fat, which is typically co-located with white fat, can exhibit either storage or thermogenic properties, depending on environmental conditions. It also exerts anti-inflammatory properties via induction of interleukin 4, an anti-inflammatory molecule. White fat can convert to beige fat, a process known as “beiging.” Findings described in a recent report suggest that beige fat mediates the neuroprotective effects of subcutaneous fat.
Subcutaneous fat, which is composed of both white and beige fat, is stored just beneath the skin. Commonly associated with a “pear” shape, it may protect against dementia. Visceral fat, on the other hand, is composed of white fat. It is stored in the abdominal cavity close to internal organs such as the liver, pancreas, and intestines. An excess of visceral fat, often referred to as central obesity or abdominal obesity, is commonly associated with an “apple” shape and an increased risk for chronic disease, including dementia.
The authors of the report conducted a two-part study using a type of mouse genetically modified to lack the gene that promotes beiging. Without beiging, subcutaneous fat behaves more like visceral fat.
In the first part of the study, they fed either a low-fat or high-fat diet to the genetically modified mice and normal mice for one month. They tested the animals' cognitive function and measured markers of inflammation and immune activation. Both groups of mice became obese on the high-fat diet, but cognitive tests revealed that the mice without beige fat showed signs of early cognitive impairment while the normal mice did not. The mice without beige fat also exhibited rapid, robust inflammatory responses to the high-fat diet, including activation of microglial cells (a type of immune cell found in the brain). Microglia activation promotes inflammation, harms brain health, and contributes to dementia.
In the second part of the study, the authors transplanted subcutaneous fat from young, lean healthy mice into the abdominal areas of the obese, cognitively impaired mice. The recipient mice experienced improvements in memory and synaptic plasticity – the ability to form new connections between neurons.
These findings suggest that beige fat drives the neuroprotective and anti-inflammatory effects of subcutaneous fat in mice. A growing body of evidence suggests that cold exposure promotes beiging of white fat. Learn more about the health effects of cold exposure in our overview article.
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The body mass index (BMI) is a ratio of weight to height and is one tool for measuring body size in health care and research. Epidemiological research indicates that individuals with a healthy BMI (between 20 and 25) have the lowest risk of cardiovascular disease and death compared to individuals with underweight (BMI less than 18.5), overweight (BMI between 25 and 30), and obesity (BMI greater than 30); however, some people with a healthy BMI experience metabolic dysfunction and an increased risk of death. Authors of the following report explore the condition lipodystrophy, its physiological causes, and its prevalence in the general population.
Lipodystrophy is a condition in which the amount and/or distribution of fat tissue in the body is abnormal. Visceral fat is fat stored in the abdomen and is associated with insulin resistance, elevated triglycerides, and fatty liver. This is in contrast to fat stored in the lower body, called subcutaneous fat, which is not associated with metabolic dysfunction. In short-term studies, people with a healthy BMI and an increased waist-to-hip ratio (i.e., ratio of visceral to subcutaneous fat) are at a three times greater risk of death than people with obesity and no metabolic dysfunction, a condition referred to as metabolically healthy obesity. However, long-term studies (those with greater than 10 years' follow-up) show that people with metabolically healthy obesity have a 24 percent increased risk of death, suggesting metabolically healthy obesity is a transient stage between metabolic health and metabolic disease.
The authors recruited almost 1,000 Caucasian/white participants of varying weight status who were at an increased risk of cardiometabolic disease based on weight, family and personal history of diabetes, and elevated glucose levels. The researchers used magnetic resonance imaging (MRI) to precisely measure body fat amount and distribution. They also measured blood pressure, fasting triglyceride levels, fasting glucose, the inflammatory marker C-reactive protein, insulin resistance, and carotid intima thickness (a measure of atherosclerosis). They defined good metabolic health as having two or fewer of the following criteria: blood pressure greater than 130/85 millimeters of mercury or the use of blood pressure medication; fasting triglycerides greater than 150 milligrams per deciliter; fasting HDL cholesterol (i.e., good cholesterol) less than 40 milligrams per deciliter in males or less than 50 milligrams per deciliter for females; fasting glucose greater than 100 milligrams per deciliter or the use of diabetic medication; C-reactive protein level in the 90th percentile or above; or insulin resistance in the 90th percentile or above.
Compared to people with a healthy BMI and good metabolic health, those with a healthy BMI and more than two metabolic risk factors had more insulin resistance, nonalcoholic fatty liver disease, visceral obesity, less lower body subcutaneous fat, and increased atherosclerosis. However, they did not have an increased prevalence of high blood pressure, high triglycerides, low good cholesterol, or increased inflammation. Compared to people with a healthy BMI and metabolic dysfunction, people with overweight or obesity and metabolic dysfunction had a gradual increase in the prevalence of visceral adiposity, fatty liver, insulin resistance, atherosclerosis, and low subcutaneous fat volume in the lower body as BMI increased. This means that metabolic dysfunction in people with a healthy BMI is most characterized by insulin resistance and atherosclerosis and is most strongly associated with lower subcutaneous fat in the lower body than visceral adiposity in the abdomen. The authors used this to support the existence of a lipodystrophy phenotype in people with a healthy BMI.
The authors conclude that some people with a healthy BMI may still have lipodystrophy that puts them at an increased disease risk compared to individuals with a healthy BMI and normal fat distribution. They recommend early testing of insulin sensitivity and use of medications that increase insulin sensitivity in people with lipodystrophy to lower disease risk.
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Exercise benefits people who have more than one chronic disease by disrupting inflammation from visceral fat www.inverse.com
People living with two or more chronic diseases – a condition known as multimorbidity – are more likely to take multiple medications, have more frequent and longer hospital stays, and die prematurely than those with only one chronic disease. Multimorbidity is common among older adults.60240-2/fulltext) Findings from a recent meta-analysis suggest that exercise benefits people with multimorbidity.
Evidence indicates that exercise increases muscle strength, improves cardiovascular and metabolic health, and boosts mood by reducing visceral fat mass and activating a wide range of anti-inflammatory processes in the body. A key feature of many chronic diseases is inflammation, but exercise may disrupt inflammation to elicit its beneficial effects.
The authors of the meta-analysis reviewed data from 23 randomized controlled studies that investigated the health effects of exercise in people with multimorbidity, defined as having two or more chronic health conditions (arthritis of the knee or hip, hypertension, type 2 diabetes, depression, heart failure, ischemic heart disease, or chronic obstructive pulmonary disease). The study participants were between the ages of 50 and 80 years. The average duration of the studies was 12 weeks and included a variety of exercise protocols, including aquatic exercise, strength training, aerobic training, and tai chi, performed two to three times per week.
The analysis revealed that exercise therapy interventions improved physical fitness (determined by walking distance and speed) and decreased symptoms of anxiety and depression, especially among younger adults. The interventions didn’t increase knee, arm, or back pain, or falls and fatigue. Study participants who engaged in regular exercise were less likely to be hospitalized, develop pneumonia, or experience extreme fatigue.
These findings suggest that exercise exerts beneficial effects on people with multimorbidity and serves as a viable option in managing their conditions.
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Consuming carotenoid-rich vegetables reduces visceral body fat in obese men. pubmed.ncbi.nlm.nih.gov
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.
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Increased visceral fat impairs cognition through chronic microglial activation mediated by IL-1 beta release [animal research] www.sciencedaily.com
Scientists find that visceral fat, a type of adipose tissue that produces high levels of inflammatory signals known as adipokines, impair learning and memory in mice by setting off an inflammatory cascade mediated by the release of IL-1 beta, which crosses the blood-brain barrier leading to chronic activation of microglia.
From the article:
“We have identified a specific signal that is generated in visceral fat, released into the blood that gets through the blood brain barrier and into the brain where it activates microglia and impairs cognition.”
Visceral fat as the ring leader:
They looked further and found that just transplanting the visceral fat caused essentially the same impact as obesity resulting from a high-fat diet, including significantly increasing brain levels of interleukin-1 beta and activating microglia. Mice missing interleukin-1 beta’s receptor on the microglia also were protected from these brain ravages.
[…]
To measure cognitive ability, the scientists looked at mice’s ability to navigate a water maze after 12 weeks on a high- or low-fat diet. They found it took the normal, or wild type, mice consuming the higher fat diet as well as the visceral transplant recipients with NLRP3 intact longer to negotiate the water maze. In fact, while they could reach a platform they could see, they had trouble finding one beneath the water’s surface that they had been taught to find. Mice with the interleukin-1 receptor knocked out, could find it just fine, Stranahan says.
The high-fat diet, transplant mice also had weaker connections, or synapses, between neurons involved in learning and memory. Mice on a high-fat diet but missing NLRP3 were spared these changes, like mice on a low-fat diet.
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As a cofactor in the biosynthesis of carnitine, vitamin C may have a role in enhancing PPAR-alpha-dependent fatty acid oxidation www.nature.com
From the publication:
Ascorbic acid is a known cofactor in the biosynthesis of carnitine, a molecule that has an obligatory role in fatty acid oxidation […] Ascorbic acid supplementation increased the mRNA levels of PPARα and its target enzymes involved in fatty acid β-oxidation in visceral adipose tissues. Consistent with the effects of ascorbic acid on visceral obesity, ascorbic acid not only inhibited hepatic steatosis but also increased the mRNA levels of PPARα-dependent fatty acid β-oxidation genes in livers. Similarly, hepatic inflammation, fibrosis, and apoptosis were also decreased during ascorbic acid-induced inhibition of visceral obesity. In addition, serum levels of alanine aminotransferase, aspartate aminotransferase, total cholesterol, and LDL cholesterol were lower in HFD-AA-fed mice than in those of HFD-fed mice.
A few bullet points:
- Reduced visceral obesity
- Reduced hepatic inflammation
- Increased expression of PPAR-a
- Improved markers of liver health and cholesterol
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Excess visceral fat promotes inflammation and drives cognitive decline. www.eurekalert.org
Visceral fat – body fat that is stored in the abdominal cavity in close proximity to important internal organs such as the liver, pancreas, and intestines – plays a central role in the interrelationship between obesity and systemic inflammation. Excess visceral fat, often referred to as central or abdominal obesity, is a strong predictor of age-related cognitive decline. A new study in mice demonstrates that having excess visceral fat may impair cognition by activating the NLRP3 inflammasome and promoting the release of interleukin-1 beta (IL-1β).
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. Cryopyrin, also known as NLRP3, is a protein that drives the formation and activation of the NLRP3 inflammasome.
Interleukin-1 beta is a proinflammatory protein present in many cells. NLRP3 inflammasome-driven release of IL-1β activates microglia, the brain’s resident immune cells. Microglia serve an essential role in maintaining brain microenvironment homeostasis. Acute activation of microglia modulates inflammation and neurotoxicity, but chronic activation promotes brain inflammation and harm.
The authors of the study first determined that mice lacking the gene for NLRP3 did not experience visceral fat-induced brain inflammation and cognitive decline. They also determined that when visceral fat from normal, obese mice was transplanted into these mice, they exhibited higher levels of IL-1β in their hippocampus, an area of the brain associated with memory (in particular, the consolidation of short-term memories to long-term memories), learning, and spatial navigation.
To understand the effects of IL-1β on brain function, the authors of the study fed the mice a high- or low-fat diet for 12 weeks and then assessed the animals' capacity to navigate a water maze. The mice that ate the higher-fat diet experienced greater difficulties negotiating the water maze, compared to those that ate the lower-fat diet. Examination of the animals' brains revealed that the mice that ate the high-fat diet (as well as those that received the fat transplants) had weaker synapses between the neurons involved in learning and memory.
These findings suggest that chronic inflammation driven by excess visceral fat may contribute to cognitive decline by promoting the release of IL-1β and increasing inflammation. Inflammation drives other aspects of brain dysfunction, including those associated with depression. Watch this clip in which Dr. Charles Raison discusses how a pro-inflammatory environment can contribute to the risk of depression.
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Sulforaphane (found in broccoli sprouts) causes 20% fat loss by changing gut bacteria & increasing mitochondria in fat in mice. www.sciencedaily.comGut Obesity Microbiome Metabolism Inflammation Sulforaphane Fatty Liver NRF2 Endotoxemia Lipopolysaccharide Visceral Fat
Sulforaphane from broccoli sprouts causes 20% visceral fat loss by changing gut bacteria and increasing mitochondria in fat in mice. The mice fed sulforaphane also lowered fatty liver and reduced blood glucose levels. Sulforaphane reduced inflammation by decreasing a species of bacteria in the gut that is responsible for producing endotoxin, which is a major source of inflammation. Also, sulforaphane increased the levels of UCP1, which is responsible for increasing mitochondrial biogenesis (the generation of new mitochondria) in fat (called browning of fat). The browning of fat increases fat metabolism and can lead to fat loss. There have been human studies showing that sulforaphane decreases inflammatory biomarkers and improves blood glucose levels. It will be interesting to see future studies looking at these two new functions of sulforaphane in humans. For more information check out my video on sulforaphane or my podcast with Dr. Jed Fahey, who discovered broccoli sprouts are the best source of sulforaphane. Sulforaphane video: https://youtu.be/zz4YVJ4aRfg Sulforaphane podcast: https://youtu.be/Q0lBVCpq8jc