Browse the evidence

Dietary habits are the dominant factor explaining inter-individual variation in the plasma metabolome, accounting for more variance than genetics or the gut microbiome for the majority of metabolites.

Your diet has a significantly larger impact on your blood metabolite levels than your genetics or gut bacteria do for most metabolic markers. Focusing on food quality and specific food items (like coffee or fish) can directly alter your metabolic profile more effectively than trying to change your genetic makeup.

Plasma metabolite levels can accurately predict an individual's diet quality score, reflecting the relationship between diet and disease.

You can use blood metabolite profiles to objectively assess your diet quality, providing a more accurate picture than self-reported food surveys alone.

Bariatric surgery is the most effective long-term treatment for obesity, providing durable weight loss and resolution of comorbidities where conventional lifestyle and pharmacological interventions fail.

If you have a BMI over 40, or over 35 with health issues like diabetes or high blood pressure, and standard diet and exercise efforts haven't worked, bariatric surgery is the most effective option for lasting weight loss and fixing related health problems. It involves surgery that either restricts stomach size or alters digestion, and requires lifelong vitamin monitoring.

Bariatric surgery significantly reduces overall mortality in obese patients, including those with and without diabetes, compared to non-surgical management.

For severely obese individuals, surgery not only helps lose weight but also significantly extends life expectancy by reducing the risk of death from obesity-related causes like heart disease and diabetes, often more so than non-surgical management.

Ultrasound-measured muscle thickness (MT) is a valid and reliable proxy for MRI-measured anatomical cross-sectional area (ACSA) at a specific site (mid-thigh) following resistance training, but it does not accurately predict changes in total muscle volume (VOL) due to regional hypertrophy.

If you are tracking muscle growth using ultrasound, measure muscle thickness at the mid-thigh (50% of femur length). It is a reliable indicator of local muscle area growth after 12 weeks of resistance training. However, do not assume this thickness increase equals a proportional increase in your total leg volume, as muscles grow unevenly (regionally).

Physical activity reduces the risk of colon cancer (especially in men) and breast cancer (especially in post-menopausal women), with consistent evidence for lung and endometrial cancers.

Regular physical activity is a proven way to reduce your risk of several cancers, including colon cancer (especially for men) and breast cancer (especially for post-menopausal women). It also reduces the risk of lung and endometrial cancers. Make activity a regular part of your life.

Core circadian clock genes (specifically Cry1, Cry2, Bmal1, Npas2, and Per1/Per2) regulate sleep homeostasis by modulating the buildup and dissipation of sleep pressure, as evidenced by altered EEG delta power and sleep duration in knockout models.

Your body's internal clock genes (like PER and CRY) don't just tell time; they track how long you've been awake. This tracking mechanism directly influences sleep pressure (measured by EEG delta power). To optimize sleep homeostasis, maintain consistent sleep-wake times to align with these molecular rhythms, as disruptions can alter how quickly sleep pressure builds up and dissipates.

Oral intake of bacterial probiotics (specifically multispecies mixes containing Bifidobacterium breve, B. longum, Streptococcus salivarius subsp. thermophilus, Lactobacillus acidophilus, L. casei, or L. delbrueckii) induces minor but statistically significant reductions in body weight, BMI, waist circumference, and visceral adipose tissue in overweight (but not obese) subjects.

If you are overweight, adding a multispecies probiotic supplement (containing strains like L. acidophilus or B. breve) to your daily routine may help you lose a small amount of weight (less than 1 kg on average) and reduce waist size over 8 weeks. This effect is not seen in obese individuals. Do not rely on probiotics alone for weight loss; use them as a minor adjunct to diet and exercise.

Urinary nitrogen excretion is a more stable and practical independent marker for assessing habitual protein intake than dietary records, requiring fewer collections to achieve the same level of confidence.

For accurate assessment of habitual protein intake, consider using objective markers like urinary nitrogen, which are more stable and less variable than self-reported dietary records.

A hypertensive response to exercise (HRE) at moderate intensity is an independent predictor of cardiovascular events and mortality, whereas HRE at maximal intensity is not significantly associated with increased risk.

If you undergo an exercise stress test, pay attention to your blood pressure response at moderate effort, not just at your maximum. An exaggerated rise in blood pressure during moderate exercise is a significant warning sign for future heart problems, even if your blood pressure is normal when you are sitting still. This finding is independent of your age and other risk factors, so discuss these results with your doctor to determine if further cardiovascular evaluation is needed.

Vigorous leisure-time physical activity is associated with higher heart rate variability (HRV) and lower resting heart rate in men, serving as a mechanism for reduced coronary heart disease risk.

For men, engaging in vigorous leisure-time activity (like jogging or tennis) is strongly linked to better heart health markers (HRV) and lower resting heart rate. However, moderate activities (like walking or gardening) also contribute to these benefits. If you are overweight, vigorous activity may help bring your HRV levels closer to those of normal-weight individuals, though it may not fully surpass the benefits of having a low BMI. Focus on accumulating weekly volume of activity, regardless of intensity, to support autonomic function.

In overweight or obese men (BMI > 25), high levels of vigorous activity are associated with HRV levels similar to those of normal-weight men who do not engage in vigorous activity.

If you are overweight, engaging in vigorous activity can significantly improve your heart's autonomic function (HRV), bringing it in line with that of normal-weight people who don't exercise. However, it may not fully replace the benefits of having a lower BMI. Prioritize consistent activity for heart health, but recognize that weight management may offer additional autonomic advantages.

Metabolic flexibility—the ability of skeletal muscle to switch between fat and glucose oxidation in response to fasting and insulin—is a key determinant of insulin sensitivity and leanness.

To improve metabolic health, focus on building aerobic fitness and maintaining leanness. These factors enhance your muscles' ability to switch between burning fat and glucose, which is crucial for insulin sensitivity. Simply losing weight without improving fitness may not restore this flexibility.

Moderate weight loss alone, without concurrent improvement in aerobic fitness, fails to restore the capacity for fat oxidation in overweight and obese individuals, although it may improve insulin's suppression of fat oxidation.

If you lose weight without exercising aerobically, your muscles may still struggle to burn fat efficiently. To fully restore metabolic flexibility, combine weight loss with aerobic fitness training.

Rotating shift work involving night shifts causes significant sleep loss, increased sleepiness, and reduced performance due to circadian misalignment, with negligible long-term physiological adaptation.

If you work night shifts, expect to be sleepier and less accurate, especially in the early morning hours. Your body will not fully 'get used to' this over time. Prioritize sleep hygiene and consider requesting schedule rotations that move forward (morning to night) rather than backward, as this is biologically easier.

Night shift work is associated with a significantly higher risk of single-vehicle accidents, particularly in the early morning hours, due to fatigue-induced performance lapses.

Driving or operating machinery during the early morning hours (e.g., 2 AM - 5 AM) after a night shift carries a high risk of accident due to fatigue. If possible, avoid driving immediately after a night shift or ensure adequate rest before operating vehicles.

Low BMI (<17.5) is associated with an increased risk of cardiovascular disease mortality in East Asians, creating a U-shaped relationship with CVD death.

For East Asians, being underweight (BMI <17.5) is associated with a significantly increased risk of cardiovascular death. Aim for a BMI between 20.0 and 22.4, which is associated with the lowest risk. Avoid extreme thinness, as it may indicate underlying health issues or low muscle mass that increases CVD risk.

Sarcopenic obesity (low muscle mass + high visceral fat) carries a significantly higher risk of metabolic syndrome and adverse health outcomes than either condition alone.

If you have excess belly fat but low muscle strength, your risk for metabolic syndrome is extremely high. Focus on resistance training to build muscle while managing diet to reduce visceral fat, rather than just losing weight.

Adherence to a Mediterranean dietary pattern (MeDi) is associated with a decreased risk of dementia and better cognitive performance, particularly in memory, language, and visuospatial domains, in elderly populations.

To support cognitive health and potentially lower dementia risk, aim for a Mediterranean dietary pattern. This involves high consumption of non-refined cereals, fruits, vegetables, legumes, fish, and olive oil, while limiting red meat and full-fat dairy. In this study, each unit increase in adherence score was linked to a 10% decrease in dementia odds, with the strongest benefits seen in memory and language functions. Start by incorporating more fish and whole grains into your weekly meals.

High body fat percentage (BFP) and high visceral adipose index (VAI) are significantly associated with increased risk of overweight/obesity and abdominal obesity, whereas smoking and alcohol consumption are not associated with these conditions in southern China.

Focus on body composition rather than just weight. If you have a normal BMI but a high waist circumference or body fat percentage, your risk for metabolic issues is still elevated. Regularly monitoring waist circumference and body fat percentage is more informative than BMI alone for assessing obesity-related risks.

Higher consumption of an unhealthy 'Western' dietary pattern is independently associated with smaller left hippocampal volume in older adults, while higher consumption of a healthy 'prudent' dietary pattern is associated with larger left hippocampal volume.

Focus on eating a 'prudent' diet rich in vegetables, fruit, whole grains, and fish, while minimizing 'Western' foods like processed meats, fried foods, and sugary drinks. This dietary pattern is associated with larger hippocampal volume, a brain region critical for memory and mood, in older adults.

Reducing total fat intake in children and adolescents to 28-34% of energy does not compromise growth or development, provided total energy and essential nutrient intakes are adequate.

For children over 2, you can safely reduce fat to about 30% of calories without worrying about stunted growth, as long as they are eating enough total food and getting enough protein. Do not restrict fat in infants under 2.

In male patients, abdominal (waist) circumference is a closer independent correlate of OSA severity (AHI) than neck circumference or BMI, whereas in female patients, neck circumference is the best anthropometric correlate.

Body shape matters for OSA risk assessment differently for men and women. For men, waist size is a better indicator of OSA severity than neck size. For women, neck size remains the key anthropometric indicator. Doctors should account for these sex-specific differences when assessing risk.

Both exercise alone and combined exercise/diet interventions significantly improve knee pain, disability, and physical performance in older adults with knee osteoarthritis, with no significant between-group differences in pain scores.

Starting an exercise program is beneficial for reducing knee pain and improving function in older adults with osteoarthritis, regardless of whether they lose weight. You do not need to lose weight to get pain relief from exercise, although losing weight may offer additional biomechanical benefits.