Browse the evidence

Depression and insomnia are associated with specific alterations in gut microbiota composition, including decreased Bacteroidetes and increased Firmicutes/Actinobacteria, suggesting a bidirectional link between mental health and gut ecology.

If you have depression or insomnia, your gut health may be a contributing factor. While not a cure-all, addressing gut health through diet and potentially probiotics may support mental health treatment.

GLP-1 analogs improve skeletal muscle glucose metabolism and glycogen synthesis through non-canonical signaling pathways independent of cAMP.

GLP-1 analogs may help your muscles use glucose more efficiently through a separate pathway than in the pancreas. This contributes to better blood sugar control and energy storage as glycogen.

GLP-1-based therapies (GLP-1 receptor agonists and DPP-4 inhibitors) are associated with a class-wide risk of acute pancreatitis, driven by a mechanism of supraphysiological GLP-1 receptor activation causing exocrine pancreatic duct proliferation and potential occlusion.

If you are taking a GLP-1 drug (like Ozempic, Trulicity, or Victoza) or a DPP-4 inhibitor (like Januvia), be aware of the potential risk of pancreatitis. If you experience severe, persistent abdominal pain, stop the medication and seek medical attention immediately. The paper suggests this risk is real and mechanistically plausible, not just a rare side effect.

GLP-1-based therapies are associated with an increased risk of thyroid cancer, specifically medullary thyroid cancer and papillary thyroid cancer, due to GLP-1 receptor expression in thyroid C-cells and papillary cancer cells.

If you are taking a GLP-1 drug, be aware of the potential risk of thyroid cancer. If you notice a lump in your neck, hoarseness, or difficulty swallowing, seek medical attention immediately. The paper suggests this risk is real and mechanistically plausible, not just a rare side effect.

Heterozygosity for UCP2 exon 4 (Ala/Val) and exon 8 (ins/del) polymorphisms is associated with significantly higher sleeping metabolic rate and 24-hour energy expenditure in young Pima Indians.

Your genetics (specifically UCP2 variants) might give you a slightly higher metabolic rate if you carry certain heterozygous forms, burning roughly 100-150 extra calories a day at rest. However, this effect is small and accounts for only a tiny fraction of your total metabolic variation. Focus on controllable factors like diet and exercise, as your genes are not a barrier to weight management.

The UCP2 exon 8 insertion/deletion polymorphism is associated with lower Body Mass Index (BMI) in Pima Indians over the age of 45, specifically in heterozygotes.

If you are over 45, carrying the heterozygous form of the UCP2 exon 8 polymorphism might help you maintain a lower BMI over time, likely due to a higher metabolic rate. This effect is not seen in younger people, suggesting it takes decades to manifest in body composition.

LSG increases the excretion of nonesterified fatty acids (NEFAs) and alters bile acid metabolism, leading to increased malabsorption of energy-rich substrates, whereas VLCD does not significantly alter faecal fatty acid excretion.

Surgery (LSG) physically changes how your body handles fat, causing you to excrete more of it rather than absorbing it. This malabsorption contributes to weight loss independently of how much you eat.

VLCD increases the microbial metabolic capacity for butyrate fermentation, whereas LSG decreases it, despite no significant change in actual faecal butyrate concentrations for either group.

Dieting (VLCD) trains your gut bacteria to be more efficient at producing butyrate, a beneficial short-chain fatty acid. Surgery (LSG) reduces this efficiency. However, because you aren't eating much fiber, you don't necessarily see more butyrate in your stool.

Reducing total dietary fat intake over the past 30 years in the US has not led to a reduction in obesity prevalence, suggesting that fat reduction alone is insufficient for weight control without addressing total energy intake and physical activity.

Cutting fat alone hasn't stopped obesity rates from rising. To manage weight, focus on total energy intake and physical activity, not just the fat content of your food.

Calorie restriction reduces oxidative damage to macromolecules (DNA, proteins, lipids) and down-regulates the insulin/IGF-1/mTOR signaling pathways, which are key mechanisms for extending healthspan and lifespan.

While CR reduces oxidative stress and IGF-1 signaling, these are downstream effects of the metabolic state. You cannot simply take antioxidant supplements to achieve these benefits; the hormonal and metabolic shifts require actual caloric restriction.

High intake of long-chain n-3 (LCn3) omega-3 fatty acids does not significantly reduce all-cause mortality, cardiovascular mortality, or major cardiovascular events compared to low intake in primary or secondary prevention populations.

If you are trying to prevent heart disease or have existing heart conditions, increasing your intake of long-chain omega-3 fatty acids (from fish or supplements) is unlikely to significantly lower your risk of death or heart events on its own. Focus on proven strategies like managing blood pressure, cholesterol, and blood sugar, and maintaining a healthy weight.

Fetal undernutrition programs metabolic efficiency that becomes maladaptive in overnourished environments, leading to abnormal lipid profiles, altered glucose/insulin metabolism, and obesity.

Early life nutrition (fetal and infant) can program metabolic efficiency that predisposes individuals to obesity and diabetes if they later consume an overnourished diet. Public health should consider early life interventions.

Exercise training prevents the development of Nonalcoholic Steatohepatitis (NASH) and liver fibrosis by suppressing chronic inflammation and downregulating scavenger receptors in Kupffer cells.

If you have fatty liver, exercise is a primary treatment to reduce liver inflammation and scarring, working alongside dietary changes.

Olive oil polyphenols (specifically oleuropein and hydroxytyrosol) act as caloric restriction mimetics by activating sirtuins (Sirt1), AMPK, and Nrf2 pathways, thereby inducing autophagy and reducing inflammation without actual caloric restriction.

Incorporate high-polyphenol extra virgin olive oil into your diet regularly. This provides compounds that mimic the cellular benefits of caloric restriction, such as improved metabolic health and reduced inflammation, without needing to drastically reduce food intake.

Olive polyphenols (oleuropein and hydroxytyrosol) exhibit anti-cancer properties by inducing apoptosis, inhibiting angiogenesis, and preventing metastasis in various cancer cell types, including breast, prostate, and pancreatic cancer.

While not a cure, consuming olive oil rich in polyphenols may support cancer prevention and potentially enhance the effectiveness of certain treatments. Focus on high-quality EVOO as part of a balanced diet.

The effect of MUFA on Coronary Heart Disease (CHD) events is ambiguous, with some meta-analyses showing increased risk and others showing decreased risk.

While MUFA improves risk factors like blood pressure and lipids, its direct impact on preventing heart attacks is not yet clearly proven in long-term observational studies, so it should be part of a broader healthy diet rather than a standalone cure.

Randomizing the stereospecific position of fatty acids in triacylglycerols (TAGs) alters postprandial lipid metabolism and clearance rates compared to native fats, potentially affecting cardiovascular risk factors like atherogenicity and thrombogenicity.

When choosing fats, consider that how they are processed (e.g., interesterification or randomization) can change how your body digests and clears them from your blood after a meal. While this doesn't necessarily change your fasting cholesterol numbers, it may impact your post-meal lipid response. For infants, matching the fat structure to human milk (placing palmitic acid at the sn-2 position) improves absorption and reduces calcium loss.

Young men are the only demographic group capable of retaining a significant portion of muscle volume gains after 31 weeks of detraining.

If you are an older adult or a woman, be aware that you may lose most of your muscle gains after 31 weeks of stopping training. Young men might retain some, but consistent training is necessary for everyone to maintain muscle mass.

Sub-clinical gut microbiome dysbiosis, characterized by decreased Akkermansia muciniphila and increased oxidative stress resistance pathways, serves as an early biomarker for obesity and type 2 diabetes prior to clinical onset.

This research suggests that gut health changes occur before blood sugar or weight issues become clinically apparent. Monitoring gut health markers like Akkermansia levels could potentially offer early warnings for metabolic health risks, allowing for proactive lifestyle adjustments.

Global adherence to the Mediterranean dietary pattern has significantly declined since the 1960s, driven by a disproportionate increase in the availability of non-Mediterranean foods (meat, sugars, vegetable oils) relative to traditional Mediterranean staples.

If you are trying to follow a Mediterranean diet, be aware that global food systems are actively working against you by making non-Mediterranean foods (meat, sugar, refined oils) more available and affordable than traditional staples. To maintain adherence, you must consciously prioritize the availability of Mediterranean foods (olive oil, vegetables, legumes) and limit the intake of the 'western' foods that are increasingly dominating global food supplies.

Gut microbiota-derived short-chain fatty acids (SCFAs) regulate host appetite by binding to G-protein-coupled receptors (FFAR2/FFAR3) to stimulate the secretion of anorexigenic hormones (GLP-1, PYY) and directly acting on hypothalamic neurons.

To leverage gut bacteria for appetite control, consume diverse sources of dietary fiber that ferment into short-chain fatty acids (SCFAs). These metabolites signal satiety hormones like GLP-1 and PYY. Because responses vary by individual microbiota and fiber type, focus on consistent, varied fiber intake rather than a single 'magic' fiber source.

Gut microbiota-derived bacterial protein ClpB acts as a molecular mimic of alpha-MSH, directly activating anorexigenic neurons and stimulating the secretion of satiety hormones (PYY, GLP-1) to induce satiety.

Maintaining a healthy gut microbiome through a diverse diet supports the production of beneficial bacterial proteins like ClpB. These proteins may help regulate appetite by mimicking satiety signals, though this is a secondary mechanism compared to fiber-derived SCFAs.

Cash incentives for physical activity via wearables may be less effective than charity incentives or no incentives, and can even reduce physical activity compared to control groups.

Be cautious with cash-based fitness challenges. Evidence suggests they may be less effective than charity-based incentives or no incentives, and can even reduce activity levels. Focus on intrinsic motivation or social/charitable rewards instead.

Resveratrol improves metabolic health and insulin sensitivity by activating SIRT1 and AMPK pathways, leading to increased energy expenditure and lipid mobilization, although its clinical efficacy is limited by extremely low systemic bioavailability due to rapid metabolism.

Resveratrol activates metabolic pathways like SIRT1 in lab settings, but in humans, it is metabolized so quickly that very little reaches your tissues. While it may offer minor metabolic benefits, it is not a magic bullet for weight loss or insulin sensitivity due to poor bioavailability. Focus on diet and exercise instead.