Browse the evidence

Initiating hormone replacement therapy (HRT) with conjugated equine estrogens (CEE) after established cardiovascular disease or significant years post-menopause fails to provide cardiovascular protection and may increase early adverse events, whereas initiating therapy with estradiol near the time of menopause in healthy women can slow atherosclerosis progression.

If considering hormone therapy for cardiovascular health, the timing is critical. Starting estrogen therapy shortly after menopause in healthy women may slow atherosclerosis, but starting it years later in women with existing heart disease (especially using conjugated equine estrogens) does not protect the heart and may increase early risk. The type of estrogen matters: estradiol appears more effective than CEE in slowing plaque progression in healthy women.

A 14-day very low-calorie diet (800 kcal/day) prior to laparoscopic gastric bypass reduces postoperative complication rates and perceived surgical difficulty, though it does not significantly alter operating time or short-term total weight loss.

Follow the prescribed 800-calorie liquid diet exactly for the two weeks before your surgery. This isn't just about weight loss; it shrinks your liver, making the surgery safer and easier for the surgeon, which significantly lowers your risk of infections and other complications after the operation. Do not skip the nutritional supplements provided with the diet.

Adherence to the DASH dietary pattern is associated with a significantly lower risk of incident gout in men, independent of traditional risk factors.

For men at risk of gout, adopting a DASH-style diet—emphasizing fruits, vegetables, whole grains, and low-fat dairy while limiting red meat, sweets, and sodium—is associated with a significantly lower risk of developing gout. This approach is preferred over restrictive low-purine diets because it is more sustainable and also improves cardiovascular health.

Adherence to a Western dietary pattern is associated with a significantly increased risk of incident gout in men.

Men should limit their intake of red/processed meats, sugar-sweetened beverages, sweets, desserts, French fries, and refined grains, as this Western dietary pattern is associated with a higher risk of developing gout. Substituting these with fruits, vegetables, whole grains, and low-fat dairy can mitigate this risk.

Post-menopausal women exhibit 'anabolic resistance' to bone-loading exercise due to estrogen depletion, resulting in negligible increases in bone mass, although exercise can still preserve bone strength and mitigate loss.

If you are post-menopausal, do not expect exercise to significantly increase your bone density due to hormonal changes. However, continue weight-bearing and resistance exercise to maintain bone strength, improve balance, and reduce fracture risk. Focus on preservation and strength rather than mass gain.

Continuous Glucose Monitoring (CGM) metrics, specifically Time in Range (TIR) and Glycemic Variability (GV), provide superior clinical insight and safety compared to HbA1c alone by detecting hypoglycemia and glucose excursions that HbA1c misses.

If you have diabetes, rely on CGM data (Time in Range) alongside HbA1c. HbA1c tells you the average, but CGM shows the dangerous swings and lows that average numbers hide. Use this data to adjust diet and medication to stay in the 70-180 mg/dL range as much as possible.

Newer glucose-lowering agents (ultra-long-acting insulin analogs, SGLT2 inhibitors, GLP-1 RAs) reduce Glycemic Variability (GV) and hypoglycemia risk compared to older agents (e.g., insulin glargine 100U/mL) due to smoother pharmacodynamic profiles.

If you experience high glucose swings or frequent lows on older insulin, discuss switching to newer analogs (like Degludec or Glargine 300U) or adding SGLT2/GLP-1 agents with your doctor. These drugs are designed to work more smoothly, reducing dangerous lows and glucose spikes.

Glycemic Variability (GV), defined by a coefficient of variation (CV) >36%, is independently associated with an increased risk of hypoglycemia and diabetes-related complications, regardless of HbA1c levels.

Monitor your Glucose Coefficient of Variation (CV). If your CV is above 36%, your glucose is swinging too much, which increases complication risk. Work with your doctor to smooth out these swings using diet, exercise, or medication adjustments, even if your HbA1c looks okay.

Cross-sectional analysis of aging populations reveals a significant decline in muscle quality (strength per unit muscle mass) when muscle mass is estimated via anthropometric cross-sectional area (CSA) or DXA-derived fat-free mass (FFM), but not when estimated via 24-hour urinary creatinine excretion (CREAT).

When assessing muscle health in older adults, relying solely on limb circumference (CSA) may overestimate the decline in muscle quality compared to biochemical markers like creatinine excretion. If using circumference, expect a steeper apparent decline in efficiency (strength per kg) with age than if using more comprehensive mass estimates.

Longitudinal analysis of aging men shows no significant age-associated decline in muscle quality (strength per unit mass) when measured over 10-25 years, contrasting with cross-sectional findings.

For individuals tracking their own muscle health over decades, strength per unit of muscle mass may remain stable, contradicting the pessimistic trends often cited from cross-sectional population studies. Consistent strength maintenance is possible over time.

Implementing a beverage excise tax on sugar-sweetened and artificially sweetened beverages significantly increases their retail price and substantially reduces their volume sales, although cross-border shopping partially offsets the reduction in the taxed jurisdiction.

If you are a policy maker, a beverage tax is an effective tool to reduce sugary drink consumption. Expect prices to rise, which drives the reduction in sales. Be aware that some consumers will shop across borders, so design the tax to minimize this leakage (e.g., regional coordination) or accept that a portion of the sales reduction will be offset by out-of-city purchases.

Medium-term supervised exercise (12 weeks) in overweight/obese individuals increases fasting acylated ghrelin (AG) and subjective hunger, indicating an orexigenic drive, but simultaneously improves postprandial satiety efficiency through enhanced suppression of AG and increased late-phase GLP-1 release.

If you start a moderate-intensity exercise program (like brisk walking or jogging at 75% max heart rate) 5 days a week for 3 months, expect to feel hungrier when you wake up or between meals. This is a normal hormonal response (increased ghrelin). However, this hunger is counterbalanced by your body becoming more efficient at signaling fullness after you eat. Focus on the post-meal satiety benefits rather than fearing the fasting hunger, as this may help you maintain a calorie deficit more sustainably than dieting alone.

Long-term capsaicin supplementation (135 mg/day) increases fat oxidation and restores resting energy expenditure after weight loss, but does not prevent weight regain in moderately overweight individuals.

Taking 135mg of capsaicin daily after losing weight will help your body burn fat more efficiently, but it will not stop you from regaining weight if you eat too much. It is a metabolic support tool, not a weight-loss guarantee.

Dietary fiber interventions consistently increase Bifidobacterium spp. abundance in healthy adults, regardless of whether SCFA levels change significantly.

You can generally expect your gut bacteria to respond to fiber by increasing Bifidobacterium levels. However, this taxonomic shift does not guarantee a measurable increase in beneficial metabolites (SCFAs) in your blood or stool, as metabolic output varies by fiber type and individual microbiome.

Exercise alone is insufficient for significant weight loss but is a critical adjunct to diet for preserving fat-free mass and improving adherence.

Do not rely on exercise alone to lose weight. Use it to support your diet, preserve muscle, and improve overall health. Aim for 30 minutes of moderate activity daily.

Supplementation with a 50:50 mixture of cis-9,trans-11 and trans-10,cis-12 conjugated linoleic acid (CLA) at doses of 3.2–3.4 g/day for at least 6 months induces a modest but significant reduction in body fat mass and body weight in humans.

To potentially reduce body fat, take 3.2–3.4 grams of a 50:50 CLA mixture daily for at least 6 months. Do not expect dramatic results; the benefit is modest. This intervention works best when combined with other obesity control tools like physical activity, as CLA alone has limited impact on food intake or energy expenditure in humans compared to animal models.

The trans-10,cis-12 isomer of CLA is responsible for the modulation of body composition (reduction in body fat), whereas the cis-9,trans-11 isomer has no effect on body fat reduction.

When selecting a CLA supplement, ensure it contains the trans-10,cis-12 isomer, as this is the specific isomer responsible for body composition changes. The naturally occurring cis-9,trans-11 isomer found in dairy does not share this property.

Lower socioeconomic status (income <$10,000/year) in women is associated with significantly higher energy intake, higher percentage of energy from fat, and lower dietary restraint compared to higher income groups, while physical activity levels remain statistically similar across income groups.

For women in lower income brackets, weight management strategies should prioritize dietary quality and caloric awareness over exercise prescriptions, as this study found no significant difference in physical activity levels between income groups. Focus on reducing total energy intake and increasing dietary restraint (e.g., reducing fat percentage, increasing fruits/vegetables) is more likely to impact weight outcomes than increasing exercise volume alone.

Lower socioeconomic status is associated with lower dietary restraint, higher tolerance for weight gain, and fewer healthy weight control practices (e.g., reducing calories, increasing exercise), while unhealthy practices (e.g., fasting, laxative use) are more common but not always statistically significant.

Weight control programs for lower income women should focus on building dietary restraint and healthy weight management skills (e.g., regular weighing, reducing calories, increasing exercise) rather than assuming a lack of motivation or concern about weight. Addressing the higher tolerance for weight gain and teaching specific healthy practices can improve outcomes.

Omega-3 LC-PUFA supplementation significantly reduces inflammatory biomarkers (such as CRP, IL-6, and TNF-alpha) in patients with chronic diseases (e.g., cardiovascular disease, renal disease, diabetes) and acute conditions (e.g., sepsis, pancreatitis), but generally has no significant effect on inflammatory biomarkers in healthy individuals.

If you have a chronic inflammatory condition, omega-3 supplementation may help lower inflammatory markers. If you are healthy, you likely will not see a significant anti-inflammatory benefit from omega-3s, as your baseline inflammation is already low.

Consumer wearable devices (specifically Apple Watch) can accurately predict sleep stages (Wake, NREM, REM) and sleep-wake status by combining raw acceleration, photoplethysmography (PPG) heart rate, and a circadian 'clock proxy' feature using neural network classifiers.

If you use a smartwatch (like an Apple Watch) to track sleep, you can trust its sleep-wake detection more than previously thought, especially if it uses heart rate data. However, do not rely on it for diagnosing sleep disorders. For research or personal optimization, combining movement with heart rate variability and circadian timing models provides a robust estimate of sleep stages, bridging the gap between consumer tech and clinical science.

Ingestion of carbohydrates, proteins, and lipids stimulates enteroendocrine cells (EECs) to secrete gut hormones (GLP-1, GIP, CCK, PYY) via specific nutrient-sensing receptors and transporters, which modulates glucose homeostasis, appetite, and gastrointestinal motility.

Your gut naturally releases hormones like GLP-1 and PYY when you eat, which help regulate blood sugar and make you feel full. Eating a balanced diet with carbohydrates, proteins, and fats triggers this system. Artificial sweeteners do not trigger this response as effectively as real food.

Visceral adipose tissue accumulation is causally linked to hepatic insulin resistance and increased cardiometabolic risk, whereas subcutaneous adipose tissue accumulation is metabolically protective.

Prioritize strategies that promote subcutaneous fat storage (like lower-body resistance training) over those that might increase visceral fat. Monitor waist circumference and metabolic markers (blood sugar, lipids) rather than just total body weight, as visceral fat is the primary driver of metabolic disease.

Visceral adipose tissue promotes insulin resistance through the Portal Theory, where NEFAs and cytokines drain directly to the liver, whereas subcutaneous fat drains systemically and is diluted.

Targeting visceral fat loss is critical for metabolic health because this fat sends harmful signals directly to the liver. Exercises that reduce visceral fat (like aerobic exercise) may have outsized benefits for insulin sensitivity compared to exercises that only affect subcutaneous fat.