Browse the evidence

Bilirubin acts as a direct agonist for the nuclear receptor PPARα, binding to its ligand-binding pocket to upregulate lipid-oxidation genes (CPT1, FGF21) and inhibit lipid accumulation, thereby reducing body fat and blood glucose.

This research identifies bilirubin not just as an antioxidant, but as a functional hormone-like molecule that activates PPARα to burn fat. While you cannot simply 'take' bilirubin safely as a supplement in this context, the findings suggest that individuals with naturally higher bilirubin levels (such as those with Gilbert's Syndrome) may have a metabolic advantage regarding fat loss and glucose control due to this specific receptor activation pathway.

Resistance training induces neuromuscular junction (NMJ) remodeling similar to endurance training but to a lesser extent (approx. 15% vs 30% increase in area).

Resistance training (weight lifting) also improves the structure of your nerve-muscle connections, though not as dramatically as aerobic exercise. It still provides a beneficial structural adaptation that supports muscle strength.

Epigenetic modifications (DNA methylation, histone modification) serve as the molecular mechanism for 'muscle memory,' allowing skeletal muscle to retain information from prior environmental stimuli (like exercise or stress) and respond differently upon re-encounter.

This suggests that past exercise or dietary habits leave a molecular 'mark' on your muscles. This might make it easier to regain fitness after a break (the 'memory' effect) or explain why early-life poor nutrition has lasting effects.

Short-term manipulation of energy availability (≤5 days) triggers acute endocrine and metabolic dysregulations, but the long-term physiological effects of chronic LEA remain causally unproven due to a lack of long-duration prospective studies.

While short-term low energy availability clearly disrupts hormones, we lack long-term prospective data to definitively predict the chronic health outcomes of sustained LEA in humans.

Supplementation with Vitamin B complex (B6, B9, B12) reduces homocysteine levels, but this reduction does not necessarily translate to slower cognitive impairment or reduced dementia incidence in the general population.

Ensure adequate intake of Vitamin B6, B9 (Folic Acid), and B12, especially if you have high homocysteine levels, as deficiency is linked to vascular risks. However, do not rely on B-vitamin supplements alone to prevent dementia, as clinical trials show they do not consistently improve cognitive function or reduce dementia incidence in the general population.

Unsupervised anabolic steroid use involves cyclical polypharmacy with doses ranging from 250 to 3200 mg/week, resulting in skeletal muscle hypertrophy but accompanied by frequent physical side effects including acne, striae, and gynaecomastia.

This paper profiles unsupervised steroid users, not a safe protocol. It highlights that high-dose, cyclical steroid use combined with other drugs (polypharmacy) leads to muscle growth but also frequent physical side effects like acne and gynecomastia. Medical professionals should be aware of these physical signs to identify users.

Withdrawal from anabolic steroids frequently causes a reduction in muscle size and strength (reported by 72% of users) and reduced libido (33%), contributing to resumption of use.

Stopping steroid use often leads to a rapid loss of muscle size and strength, as well as reduced libido, which can drive users back to using steroids. This withdrawal cycle is a significant barrier to cessation.

Clenbuterol is used by 70% of steroid users as a secondary anabolic agent for its protein deposition and thermogenic properties.

Clenbuterol is frequently used by steroid users alongside steroids for fat loss and muscle preservation, often combined with ephedrine.

Insulin resistance is a key feature of PCOS, but routine clinical measurement of insulin resistance is not recommended due to the inaccuracy of currently available measures.

While insulin resistance is common in PCOS, current clinical tests for it are not accurate enough to guide individual treatment decisions. Focus on lifestyle changes (diet, exercise) which improve insulin sensitivity, rather than seeking specific insulin blood tests.

Variations in gut microbiota composition affect the absorption, distribution, metabolism, and excretion (ADME) of environmental chemicals, thereby altering individual exposure to obesogenic and diabetogenic toxins.

While you cannot easily control environmental chemical exposure, understanding that your gut health influences how your body processes these chemicals highlights the importance of maintaining a diverse microbiome. This may mitigate the internal impact of unavoidable environmental toxins, though more human research is needed to confirm specific interventions.

Certain environmental chemicals (obesogens and diabetogens) can disrupt metabolic homeostasis by acting on nuclear receptors involved in adipogenesis and insulin sensitivity.

Minimize exposure to known environmental chemicals like BPA (found in some plastics) and certain pesticides where possible. While complete avoidance is difficult, reducing exposure may lower the burden on metabolic pathways regulated by nuclear receptors.

Activation of PPARγ (via agonists like TZDs or endogenous upregulation) improves insulin resistance and metabolic homeostasis by enhancing adipose tissue expandability, reducing ectopic lipid accumulation, and promoting browning, rather than solely by reducing fat mass.

Focus on improving the health and capacity of your fat tissue rather than just trying to lose weight. Strategies that support healthy adipose tissue function (like those mediated by PPARs, e.g., through specific medications or lifestyle factors that promote adipogenesis and browning) can improve insulin sensitivity even if body weight remains stable or increases slightly. The key is preventing fat from accumulating in organs like the liver and muscles.

PPARα activation promotes fatty acid oxidation and energy expenditure, particularly in the liver and brown adipose tissue, contributing to the treatment of hypertriglyceridemia and obesity-induced insulin resistance.

PPARα activation (e.g., via fibrates) can help manage high triglycerides and improve energy expenditure. This is particularly relevant for those with metabolic syndrome.

PPARβ/δ activation reduces systemic inflammation and promotes fatty acid oxidation in skeletal muscle and brown adipose tissue, offering potential therapeutic benefits for obesity and insulin resistance.

PPARβ/δ activation shows promise for reducing inflammation and improving metabolism in muscle and fat, though it is still under clinical study.

Caloric restriction increases PPARγ expression in inguinal fat, promoting white fat browning, which may mimic some longevity benefits of caloric restriction.

Caloric restriction increases PPARγ in fat, helping it burn more energy (browning). This might be one reason CR helps you live longer and stay healthier.

Very Low Calorie Diets (VLCDs) under 800 kcal/day lead to rapid weight loss but result in significant loss of lean mass and are associated with poor long-term weight maintenance compared to moderate restriction.

Avoid diets under 800 kcal/day unless medically supervised. They cause rapid loss but are hard to maintain and may harm muscle mass. Moderate restriction (1200+ kcal) is safer and more sustainable.

Soy isoflavones can induce goitrogenic effects in individuals with pre-existing hypothyroidism or iodine deficiency, potentially advancing subclinical hypothyroidism to overt hypothyroidism.

If you have hypothyroidism, consult your doctor before consuming large amounts of soy isoflavones, as they may worsen thyroid function in some cases, especially if iodine intake is adequate.

Gut-derived hormones (CCK, GLP-1, PYY) released by enteroendocrine cells in response to nutrient ingestion activate vagal afferents and hypothalamic centers to inhibit food intake and increase energy expenditure, thereby regulating energy homeostasis.

Your body has a sophisticated biological system that regulates hunger and energy using signals from your gut. When this system is disrupted (as seen in obesity), simple willpower often fails because the biological 'stop' signals (like GLP-1 and CCK) are not functioning correctly. Effective treatments often target these specific pathways (e.g., GLP-1 agonists) to restore the body's natural ability to regulate intake and expenditure.

Repeated administration of CCK leads to desensitization and tolerance, explaining why CCK-derivatives have failed as effective long-term weight-loss treatments.

Early attempts to use CCK mimics for weight loss failed because the body builds tolerance to them. This highlights that simply flooding the system with one satiety signal is not a sustainable long-term strategy without addressing the underlying regulatory mechanisms.

Myostatin inhibition has potential therapeutic applications for Western diseases like COPD, type II diabetes, and obesity, but may have non-traditional side effects.

Myostatin inhibitors are being researched as treatments for serious conditions like COPD and muscular dystrophy. While promising, they are not yet standard care, and researchers are cautious about potential side effects on heart and fat metabolism.

Oxidized phospholipids (oxPLs) can have protective effects, including inhibition of inflammatory signaling and upregulation of antioxidant genes, under certain biological conditions.

Understand that not all oxidation products are harmful; some, like oxPLs, may have protective roles in specific contexts.

Post-liver transplantation sarcopenia (loss of skeletal muscle mass) is common and significantly increases the risk of new-onset diabetes mellitus and trends toward higher mortality, independent of pre-transplant characteristics or immunosuppression type.

If you have had a liver transplant, do not assume your muscle mass will recover on its own. This study shows that muscle loss is common after surgery and significantly increases your risk of developing diabetes. You should have your muscle mass monitored via CT scans or other methods and discuss specific strategies to preserve or build muscle with your healthcare team, as this impacts your long-term survival and metabolic health.

Deregulation of fatty acid synthase (FASN)-catalyzed de novo fatty acid biogenesis drives a 'lipogenic state' that links insulin resistance, type 2 diabetes, and cancer.

Current evidence suggests that high FASN activity contributes to insulin resistance and cancer risk. While not a direct lifestyle intervention, this highlights the importance of managing insulin levels and metabolic health, potentially through lifestyle changes that improve insulin sensitivity, as FASN is a target for future therapeutics.

Pharmacological inhibition of FASN activity may prevent or reverse insulin-related metabolic disorders and reduce cancer risk.

FASN inhibitors are not yet available, but research suggests they could be a valuable future treatment for insulin resistance and cancer. For now, focusing on insulin sensitivity through lifestyle is the best approach.