Browse the evidence

For men under 60, the rate of decline in grip strength is a more significant predictor of mortality than the absolute level of strength.

If you are under 60, don't just focus on how strong you are today. Pay attention to whether your strength is staying the same, improving, or declining. A steady decline in strength, even if you are still strong, is a warning sign for increased mortality risk. Regular strength training can help maintain or improve strength, mitigating this risk.

One year of aerobic exercise training increases functional connectivity in the Default Mode Network and Frontal Executive Network in older adults, an effect not observed at 6 months.

To improve brain network efficiency in older age, commit to a 12-month aerobic walking program. Start with 10 minutes and build up to 40 minutes, 3 times a week. Keep your heart rate at 60-75% of your maximum reserve. The benefits on brain connectivity appear after a full year, so consistency is critical.

Increased functional connectivity in the Default Mode Network and Frontal Executive Network following aerobic exercise is associated with improved executive function in older adults.

Focus on aerobic exercise not just for physical health, but for cognitive maintenance. The brain network improvements from walking directly support better executive function, such as task switching and inhibition.

Breaking up sedentary time with short breaks (e.g., standing or walking) is beneficially associated with metabolic biomarkers independent of total sedentary time and moderate-to-vigorous physical activity.

Don't just focus on reducing your total sitting time; focus on breaking it up. Stand up, stretch, or walk for a minute every 30-60 minutes. This improves metabolic health markers like blood sugar and triglycerides regardless of how much you exercise.

Dietary fiber intake increases the abundance of Akkermansia muciniphila and improves metabolic parameters in obese individuals.

Increase intake of soluble fibers, such as oligofructose, to boost Akkermansia muciniphila. This natural approach has been shown to improve metabolic health and reverse some effects of obesity in animal models, offering a safer alternative to unproven bacterial supplements.

Higher relative abundance of the gut bacterial family Christensenellaceae is robustly associated with lower body mass index (BMI), reduced visceral adiposity, and improved metabolic health markers (lower triglycerides, higher HDL).

Focus on dietary patterns that support Christensenellaceae: consume adequate fiber (resistant starch, galacto-oligosaccharides) and protein. While you cannot change your genetics, these dietary inputs can increase the relative abundance of this bacteria, which is associated with healthier body composition and metabolic markers. Do not expect a probiotic supplement to replace diet and exercise, as the mechanism is not fully understood and the bacteria are complex to culture.

Higher muscular strength is inversely and independently associated with reduced all-cause and cancer mortality in men, even after adjusting for cardiorespiratory fitness.

Prioritize resistance training for major muscle groups (upper and lower body) two or three days a week. This builds muscular strength, which is independently linked to a significantly lower risk of dying from all causes and cancer, regardless of your cardio fitness level.

Aging causes a steady decline in muscle strength (approx. 1-2% per year after age 60) primarily due to sarcopenia (loss of muscle mass and motor units), with concentric strength declining more than eccentric strength.

If you are over 60, expect your strength to naturally drop by about 1-2% each year unless you actively work to maintain it. This loss happens faster when you shorten your muscles (concentric) than when you lengthen them (eccentric). To fight this, you need to exercise, as your body can still adapt and build strength even in old age.

Nonalcoholic fatty liver disease (NAFLD) prevalence in the US adult population is approximately 19.0%, with strong independent associations to obesity, diabetes, insulin resistance, and dyslipidemia.

NAFLD is a common condition affecting nearly 1 in 5 US adults, strongly linked to obesity, diabetes, and insulin resistance. It is often silent, meaning normal blood tests do not rule it out. Focus on metabolic health through weight management and blood sugar control to reduce liver fat.

Long-term pharmacotherapy with orlistat, sibutramine, or rimonabant produces modest but statistically significant weight loss (2.9–4.7 kg) compared to placebo in adults with obesity, while improving specific cardiovascular risk factors.

Long-term use of FDA-approved anti-obesity medications (orlistat, sibutramine, rimonabant) leads to modest but real weight loss (approx. 3-5 kg more than placebo) when combined with lifestyle changes. While effective, these drugs carry specific side effect profiles (GI issues for orlistat, cardiovascular changes for sibutramine, mood disorders for rimonabant) that require monitoring and can lead to high discontinuation rates.

Higher time spent in sedentary behavior is associated with increased risk of all-cause mortality, cardiovascular disease (CVD) morbidity, and CVD mortality in adults, independent of moderate-to-vigorous physical activity (MVPA).

Minimize prolonged sitting. Break up long periods of sitting with light activity or standing. While meeting physical activity guidelines is essential, reducing total sedentary time offers additional cardiovascular protection.

High sedentary behavior is associated with an increased risk of developing type 2 diabetes mellitus, independent of demographic factors and adiposity indices, although BMI partially mediates this effect.

Reduce time spent watching TV and sitting. Each additional 2 hours of daily TV viewing increases diabetes risk by 20%. Replacing sitting with standing or walking around the home can reduce this risk.

High-intensity aerobic exercise (e.g., 80% VO2max) is required to significantly reduce LDL cholesterol and triglycerides in sedentary individuals, whereas moderate-intensity exercise primarily increases HDL cholesterol.

If your goal is to lower LDL cholesterol and triglycerides, you likely need to exercise at a higher intensity (around 80% of your max capacity) rather than just walking. Ensure you are doing enough total work (e.g., 400 calories per session, 3 times a week). If you are currently sedentary, start with moderate intensity to build a base, then gradually increase the intensity to target LDL.

Sleep durations outside the 7-8 hour range (short <6 hours or long >=9 hours) are associated with increased risks of cardiovascular disease, diabetes, depression, accidents, and mortality, with specific demographic and health factors driving these deviations.

Aim for 7 hours of sleep as a baseline, but recognize that this is not a rigid rule. If you are pregnant, have a chronic condition, or are under high stress, your body may need more or less sleep. Focus on sleep quality and consistency rather than hitting an arbitrary number. If you consistently struggle with sleep, look at external factors like work hours, stress, and health conditions before assuming it is a personal failing.

Bariatric surgery significantly reduces the long-term incidence of type 2 diabetes in obese patients compared to usual care, with an adjusted hazard ratio of 0.17.

For severely obese individuals at high risk of diabetes, bariatric surgery is a highly effective preventive measure, far superior to lifestyle changes alone. While surgery carries small short-term risks, the long-term reduction in diabetes risk is substantial and sustained.

Gut microbiome composition explains a significant proportion (4-6%) of the variance in blood triglyceride and HDL levels, independent of age, sex, and host genetics.

Your gut bacteria influence your cholesterol and triglyceride levels independently of your genes. While the effect size is moderate, targeting gut health through diet or probiotics may offer a supplementary strategy for managing lipids, particularly HDL and triglycerides.

Non-alcoholic fatty liver disease (NAFLD) is independently associated with a significantly increased risk of major cardiovascular disease (CVD) events, including fatal and non-fatal outcomes, with risk magnitude increasing with the severity of liver fibrosis.

If you have been diagnosed with NAFLD, you must undergo regular cardiovascular screening, regardless of your cholesterol or blood pressure levels. The presence of fatty liver, especially if fibrosis is present, independently increases your risk of heart attacks and stroke. Aggressive management of cardiometabolic risk factors is essential.

Current dietary guidelines and public health messaging focusing solely on total dietary fiber (TDF) intake quantities are insufficient because they fail to specify which types of fiber or food sources are required to achieve specific health benefits.

Stop counting only the total grams of fiber. Look at the source. To get specific health benefits, you need to consume specific types of fiber from specific foods (like oats for beta-glucans or vegetables for insoluble fiber). Current guidelines often fail to tell you this, so you must look at the food source, not just the number.

Long sleep duration (defined as >8 or >9 hours depending on the study) is significantly associated with increased all-cause mortality and incident cardiovascular disease, stroke, diabetes, and obesity compared to normal sleep duration.

Aim for 7-9 hours of sleep per night. If you consistently sleep more than 9 hours, be aware that this is associated with higher risks of heart disease, stroke, and mortality. Consult a doctor to rule out underlying issues like sleep apnea or depression, as long sleep may be a symptom rather than just a habit.

Creatine supplementation is not deleterious to kidney function in healthy individuals, despite common concerns linking it to kidney damage.

If you have healthy kidneys, you can take creatine safely. It does not damage kidney function, even with long-term use. The common fear of kidney damage is a myth based on confusing creatine with creatinine, a waste product that naturally rises with supplementation.

Seven-day estimated-diet records or open-ended food diaries provide individual nutrient intake values most closely associated with 16 days of weighed records, showing no significant differences in average intakes, whereas food-frequency questionnaires are not appreciably better than 24-hour recalls for ranking individuals.

If you need to know your exact nutrient intake for health reasons, a 7-day estimated record or open-ended food diary is far superior to a food-frequency questionnaire or a single 24-hour recall. While food-frequency questionnaires are popular for large studies, they fail to accurately rank individuals' habitual diets. For personal accuracy, spend one week meticulously recording what you eat, using portion size estimates or photos if possible, as this correlates closely with the gold standard of weighed records.

Long-term Roux-en-Y gastric bypass (RYGB) and vertical banded gastroplasty (VBG) induce durable, BMI-independent alterations in the gut microbiome that causally reduce fat mass deposition and shift host metabolism toward lipid oxidation.

Bariatric surgery (RYGB/VBG) causes long-lasting changes to gut bacteria that actively reduce fat storage and shift the body to burn more fat for energy. These changes persist for years and are not just due to eating less. The microbiome plays a direct causal role in reducing adiposity, independent of final BMI.

Higher adherence to a Mediterranean diet is associated with slower cognitive decline on the Mini-Mental State Examination (MMSE) in elderly individuals, but this benefit does not extend to the risk of incident dementia or performance on other specific cognitive tests (IST, BVRT, FCSRT).

For older adults, maintaining a Mediterranean-style diet (high in plants, olive oil, fish; low in meat/dairy) may help preserve global cognitive function (as measured by MMSE) over time. However, it should not be relied upon to prevent dementia diagnosis. The benefits appear to be modest and specific to certain cognitive measures, likely acting during the long pre-clinical phase of aging rather than treating active disease.

Obesity negatively impacts cancer survival and treatment outcomes, including increased toxicity, dosing challenges, and poorer quality of life.

Obesity can worsen cancer outcomes and complicate treatment. It is associated with higher mortality, recurrence, and treatment challenges. Maintaining a healthy weight before and after diagnosis is crucial for better survival and quality of life. Discuss dosing concerns with your oncologist, as full doses may be safe and necessary.