Browse the evidence

Genetic similarity strongly predicts the magnitude of abdominal visceral fat loss in response to negative energy balance and exercise.

If you are struggling to lose belly fat despite exercise and diet, your genetics may dictate a slower rate of visceral fat mobilization compared to others. However, this specific exercise protocol (moderate intensity, constant intake) is proven to reduce visceral fat significantly regardless of genetic background.

Among individuals with overweight or obesity who achieve initial weight loss (≥5%) in the first year, long-term maintenance of that weight loss (years 6-15) is significantly greater for those assigned to metformin compared to those assigned to intensive lifestyle intervention (ILS).

If you have prediabetes or are at high risk, achieving even a modest 5% weight loss in the first year is a strong predictor of long-term success. For those who achieve this, adding metformin (if prescribed) may help you keep the weight off better than lifestyle changes alone over the long haul (10+ years). It acts as a maintenance aid rather than just an initial weight loss tool.

Combining caloric restriction with physical activity significantly improves endothelium-dependent vasodilation in obese subjects, primarily by reducing insulin resistance and oxidative stress.

To improve blood vessel health in obesity, combine a moderate caloric deficit (600-800 kcal/day) with regular walking (30+ minutes, 3+ times a week) for 10-16 weeks. This dual approach improves insulin sensitivity and reduces oxidative stress, leading to better blood flow than weight loss alone.

Very-low-calorie diets (VLCDs, <800 kcal/day) significantly increase the risk of symptomatic gallstones requiring hospitalization and cholecystectomy compared to low-calorie diets (LCDs, 1200-1500 kcal/day) during commercial weight loss programs.

If you choose a very-low-calorie diet (around 500 calories/day) for rapid weight loss, be aware that your risk of developing symptomatic gallstones requiring hospital care is about three times higher than if you ate a standard low-calorie diet (1200-1500 calories). Although the absolute risk is still low, discuss this with your doctor, especially if you have other risk factors. Some studies suggest supplements like ursodeoxycholic acid might help reduce this risk.

Fatmax training does not significantly increase maximal oxygen consumption (VO2max) compared to other forms of exercise, but it does improve it in sedentary obese individuals.

Fatmax training improves cardiovascular fitness (VO2max) in obese, sedentary individuals, though the gains are modest. It is a safe starting point for those who cannot tolerate high-intensity exercise.

Carriers of the A allele of the FTO rs9939609 polymorphism experience significantly greater weight loss and fat mass reduction than TT genotype carriers when following either a high-protein/low-carbohydrate diet or a standard hypocaloric diet.

If you carry the A allele of the FTO gene, strict adherence to a hypocaloric diet (whether high-protein or standard) will likely result in greater weight loss than it does for people without this variant. Do not let the 'obesity gene' label discourage you; your biology may actually favor weight loss when you create a caloric deficit.

Intermittent fasting (IF) significantly reduces body weight, BMI, body fat mass, LDL cholesterol, and triglycerides in Chinese adults compared to control groups, but does not significantly reduce waist circumference, total cholesterol, HDL cholesterol, fasting glucose, or blood pressure.

If you are Chinese and looking to lose weight or improve lipid profiles, intermittent fasting (like 16:8 TRE or 5:2) is an effective strategy. Expect a modest weight loss (around 2kg) and improvements in LDL and triglycerides. However, do not expect IF to significantly lower your blood pressure or fasting glucose on its own. Adherence may be challenging due to typical eating patterns, so choose a protocol that fits your lifestyle.

Alternate-day modified fasting (ADMF) improves subjective sleep quality (SSQ) and reduces daytime dysfunction compared to daily calorie restriction, but does not significantly change total sleep quality (PSQI) or daytime sleepiness (ESS).

If you are an overweight woman, ADMF may help you feel more rested during the day and improve your subjective sense of sleep quality, even if it doesn't change your total sleep score or daytime sleepiness levels. Focus on the daytime benefits rather than just sleep duration.

The prevalence of moderate to severe sleep-disordered breathing (AHI ≥15) in US adults aged 30-70 increased substantially between 1988-1994 and 2007-2010, driven by the obesity epidemic.

If you snore loudly, feel excessively sleepy during the day, or have been told you stop breathing during sleep, get evaluated. The risk of having sleep-disordered breathing is higher than previously thought, especially if you are overweight or over 50. It is a treatable condition that can prevent serious heart and brain health problems.

Adherence to a traditional Mediterranean diet pattern is associated with a significant reduction in total mortality, coronary heart disease mortality, and cancer mortality.

To maximize longevity, adopt a Mediterranean dietary pattern. This means eating plenty of vegetables, legumes, fruits, nuts, and whole grains, using olive oil as your primary fat source, consuming fish regularly, and limiting meat, dairy, and sweets. Moderate wine consumption with meals is also part of this pattern. This approach is more effective for reducing mortality than focusing on single 'superfoods'.

Class II sarcopenia (skeletal muscle index more than 2 standard deviations below young adult mean) is independently associated with a significantly increased likelihood of functional impairment and physical disability in older adults, particularly women.

If you are over 60, your muscle mass relative to your body weight matters significantly for your ability to perform daily tasks. Severe muscle loss (Class II sarcopenia) doubles or triples your risk of disability. Focus on maintaining or building muscle through resistance exercise, as this is a key factor in preserving independence and functional ability in later life.

The Dietary Inflammatory Index (DII) quantifies the inflammatory potential of a diet by scoring 45 food parameters against a global composite database, where higher scores indicate a maximally pro-inflammatory diet and lower scores indicate a maximally anti-inflammatory diet.

To use the DII, you need detailed dietary data (like a 24-hour recall) covering 45 specific nutrients and food components. The score is calculated by comparing your intake of these items to a global average. A high positive score means your diet is likely pro-inflammatory (linked to chronic disease risk), while a negative score means it is anti-inflammatory. This tool is best used by health professionals to assess dietary patterns in epidemiological or clinical settings rather than as a simple daily checklist for individuals.

Dietary composition directly and rapidly alters gut microbiome composition, with plant-based diets increasing beneficial SCFA-producing bacteria (Bifidobacteria, Lactobacilli) and animal-based/high-fat diets increasing bile-tolerant anaerobes (Bacteroides, Bilophila) and pro-inflammatory pathways.

Focus on the type of food rather than just calories. Plant-based proteins (pea, whey) and fibers increase beneficial bacteria that produce anti-inflammatory short-chain fatty acids. Animal proteins and high saturated fats tend to increase bile-tolerant bacteria linked to inflammation. Prioritize whole food sources of carbohydrates (fiber) over artificial sweeteners to support a healthy microbiome.

High adherence to a Mediterranean diet is associated with increased fecal SCFAs and Prevotella abundance, while low adherence is linked to elevated urinary TMAO and increased cardiovascular risk.

Adopting a Mediterranean-style diet—rich in fiber, polyphenols, and unsaturated fats—supports beneficial bacteria (Prevotella) and reduces harmful metabolites (TMAO). This pattern is linked to lower cardiovascular risk and reduced inflammation.

Prolonged sitting time independently compromises metabolic health (increased triglycerides, glucose, waist circumference) and increases mortality risk, even in individuals who meet physical activity guidelines.

If you have a desk job, do not assume your gym session protects you from the risks of sitting. Break up your sitting time frequently (e.g., stand or walk for a few minutes every 30-60 minutes). This 'breaking up' of sedentary time has been shown to improve metabolic markers like waist circumference and triglycerides independently of total sitting time.

An expanded 131-item self-administered semiquantitative food frequency questionnaire (FFQ) provides a reproducible and valid measure of average daily nutrient intake over a one-year period in male health professionals, with correlations to diet records ranging from 0.28 to 0.86.

For large-scale health studies, a 131-item food frequency questionnaire is a valid and reproducible tool for estimating average nutrient intake over a year. It correlates well with detailed diet records for many nutrients (mean correlation 0.59-0.65) and accurately identifies individuals with high or low intake, making it suitable for epidemiological research into diet and disease.

Low-dose aspirin (75-160 mg/day) is recommended for primary prevention in individuals with a 10-year coronary heart disease risk of 10% or higher.

If your calculated 10-year risk of heart disease is 10% or higher, discuss taking low-dose aspirin (75-160 mg daily) with your doctor. The benefits of risk reduction generally outweigh the risks of bleeding for this group.

All popular diets significantly reduce the LDL/HDL cholesterol ratio by approximately 10% at 1 year, regardless of macronutrient composition.

You do not need to follow a specific low-carb or low-fat protocol to improve your cholesterol ratio. The study shows that any popular diet, if adhered to, will improve your LDL/HDL ratio by about 10%. Focus on losing weight through a diet you can sustain, as the improvement in lipids is a consequence of that adherence and weight loss, not the specific macronutrient breakdown.

Increased exposure to greenspace is associated with statistically significant reductions in physiological stress markers (salivary cortisol, heart rate, blood pressure) and all-cause mortality.

Prioritize spending time in green spaces (parks, forests, tree-lined streets) as a health intervention. This is not just about leisure; it is associated with measurable reductions in stress hormones, blood pressure, and long-term mortality risk. If you live in a deprived area, advocate for or seek out accessible green spaces, as the health benefits may be even stronger for those groups.

Increased greenspace exposure is associated with a reduced incidence of specific chronic diseases, including Type II diabetes, cardiovascular mortality, and stroke.

Living in or frequently visiting areas with higher greenness is associated with a lower risk of developing Type II diabetes and cardiovascular mortality. This suggests that environmental factors play a role in chronic disease prevention, independent of individual lifestyle choices alone.

Dietary resistant starch (RS) selectively increases the abundance of Ruminococcus bromii relatives (R-ruminococci) and Eubacterium rectale in the human gut, but this response is strictly dependent on the individual's baseline microbiota composition.

If you are adding resistant starch to your diet, expect different results based on your current gut bacteria. For most people, it boosts beneficial starch-digesting bacteria. However, if you have a gut microbiome lacking these specific bacteria, resistant starch may not ferment efficiently, leading to gastrointestinal discomfort without the metabolic benefits. Personalization of fiber type is key.

High-level adherence to a Mediterranean diet (MD) increases faecal short-chain fatty acid (SCFA) levels and enriches fibre-degrading bacteria (Prevotella, Lachnospira) regardless of whether the individual is an omnivore, vegetarian, or vegan.

To improve your gut health, focus on high adherence to a Mediterranean-style pattern rather than strict veganism. This means prioritizing high intake of cereals, fruits, vegetables, and legumes. Even if you are an omnivore, maintaining high adherence to these plant-based components is associated with increased beneficial short-chain fatty acids and a healthier microbiome profile, comparable to vegetarians.

Low adherence to a Mediterranean diet is associated with higher urinary trimethylamine oxide (TMAO) levels, a potential risk factor for cardiovascular disease, driven by microbial genera associated with animal protein/fat intake.

If you consume a diet low in Mediterranean principles (low plant diversity, high animal products), you may have higher levels of TMAO, a biomarker linked to cardiovascular risk. To mitigate this, increase your intake of fruits, vegetables, and legumes, which are associated with lower TMAO levels.

Dietary supplementation with arginine, glutamine, and cysteine precursors enhances immune function and reduces morbidity/mortality in subjects with malnutrition or infectious disease.

If you are recovering from surgery, dealing with a serious infection, or suffering from malnutrition, ensuring adequate intake of arginine, glutamine, and cysteine precursors may support your immune system and recovery. For generally healthy individuals, the evidence for extra supplementation is less clear, and balance is key to avoid negative interactions.