Browse the evidence

High levels of vigorous physical activity significantly reduce the risk of symptomatic diverticular disease in men, whereas non-vigorous activity does not.

To lower your risk of symptomatic diverticular disease, focus on vigorous exercise rather than just walking. Aim for activities that raise your heart rate significantly, such as running, jogging, bicycling, or swimming, for at least 47 hours per week (based on the highest quintile in the study). While walking is healthy, it does not appear to offer the same protective benefit against this specific condition.

The combination of low dietary fiber intake and low physical activity significantly increases the risk of symptomatic diverticular disease compared to high levels of both.

If you have a diet low in fiber and you are not physically active, your risk of developing symptomatic diverticular disease is more than 2.5 times higher than someone with high fiber and high activity. To minimize this risk, you should aim to increase both your dietary fiber intake and your level of physical activity, particularly vigorous exercise.

Optimal BMI and waist circumference thresholds for identifying cardiometabolic risk are higher in African-American women compared to white women, whereas thresholds are similar between white and African-American men.

If you are an African-American woman, standard BMI and waist circumference cutoffs for obesity and high risk may underestimate your actual cardiometabolic risk. This study suggests your optimal thresholds for identifying risk are approximately 3 kg/m2 higher for BMI and 5 cm higher for waist circumference compared to white women. For men, regardless of ethnicity, standard thresholds appear adequate. Consult a healthcare provider to determine if ethnic-specific thresholds should be used for your screening.

Increasing fish consumption to at least 2 servings per week in mid- or later life reduces the risk of coronary heart disease in women but has no significant effect in men.

If you are a woman, aiming for 2 or more servings of fish per week starting in midlife may help lower your risk of heart disease. If you are a man, this specific dietary change did not show a significant reduction in heart disease risk in this study, so you should focus on other proven heart-healthy strategies rather than relying on fish alone.

Six months of calorie restriction (10-30%) significantly enhances T-cell-mediated immune function in overweight adults, evidenced by increased delayed-type hypersensitivity and lymphocyte proliferation.

If you are overweight, restricting your calories by 10-30% for six months can boost your immune system's ability to fight off threats. This is achieved by improving T-cell function and reducing inflammatory markers like PGE2. This benefit is most pronounced with a 30% restriction.

Familiarity with the exercise modality significantly reduces the magnitude of biomarker elevation and the severity of Delayed Onset Muscle Soreness (DOMS) due to physiological adaptations.

When starting a new running routine or increasing intensity, expect significant muscle soreness and elevated biomarkers. This is normal. As you repeat the activity, your body adapts, reducing soreness and biomarker spikes, which is a sign of improved resilience.

Hyponatremia is a risk in ultra-endurance events, particularly when excessive water consumption occurs without adequate sodium replenishment, though it is uncommon in standard marathons.

During long events, monitor sodium intake alongside water. Drinking excessive plain water can lead to hyponatremia, especially in events lasting many hours. Follow event-specific hydration guidelines that account for sodium loss.

Poor diet is a leading cause of global malnutrition and chronic diseases, including diabetes, cardiovascular diseases, and specific cancers, driving 38.3 million deaths annually.

Focus on improving your overall diet quality, as poor dietary patterns are a primary driver of chronic diseases like diabetes and heart disease. Use reliable, individual-level dietary data rather than broad national supply estimates to understand your specific nutritional intake and make informed choices.

A preloaded 10-km treadmill time trial (90-min preload at 65% VO2max followed by a 10-km race) is highly reproducible for measuring endurance performance in trained runners, with a within-subject coefficient of variation of 1.00%.

For researchers studying endurance performance, using a 90-minute preload run at 65% of max oxygen uptake followed by a 10-km time trial on a treadmill provides a highly reliable measure of performance (CV ~1%). To achieve this reliability, you must strictly control the participants' diet (high-carb, low-fat) for 24 hours prior, provide a standardized breakfast 3 hours before the test, and ensure fluid intake is consistent between testing sessions. This protocol is particularly useful for detecting small changes in performance due to nutrition or training interventions in trained runners.

Consumption of fermented foods is associated with improved gut microbiome diversity, reduced inflammation, and metabolic health benefits, regardless of whether the product contains live microbes or is pasteurized.

Incorporate a variety of fermented foods (yogurt, kefir, sauerkraut, kimchi) into your diet. You do not need to worry if they are pasteurized; both live and dead microbes (postbiotics) offer benefits. If you have high blood pressure, choose lower-sodium options like yogurt or kefir over salty pickles, and consult your doctor if you are immunocompromised or have histamine intolerance.

Intensive lifestyle intervention (ILI) may be more effective for blood pressure control in individuals with higher BMI (>30 kg/m2), while frequent goal-based pharmacological monitoring may be more effective for those with lower BMI.

For patients with type 2 diabetes and high blood pressure, BMI may influence which treatment works best. Those with a higher BMI (over 30) might benefit more from intensive lifestyle changes, while those with a lower BMI might respond better to frequent monitoring and medication. Discuss your BMI and treatment options with your doctor.

A multidomain intensive lifestyle intervention (ILI) reduces the incidence of self-reported complaints about decision-making and problem-solving abilities in adults with type 2 diabetes who are overweight but not obese.

If you have Type 2 Diabetes and are overweight (but not obese), committing to a structured lifestyle program involving moderate calorie restriction and regular brisk walking (aiming for 175 minutes a week) can help protect your ability to make decisions and solve problems. This benefit was not seen in obese individuals in this study, so weight management strategies should be tailored carefully.

Modifying the Health Star Rating algorithm to penalize ultra-processed foods (via negative points or score capping) significantly improves alignment with the NOVA classification system, but reduces alignment with current Australian Dietary Guidelines for core food categories like cereals and convenience foods.

Current front-of-pack labels may give a 'health halo' to ultra-processed foods that look nutritious on paper. If you are trying to eat whole foods, look for the NOVA classification or ingredient list complexity, not just the star rating. Be aware that some 'core' foods (like instant oatmeal or plant milks) are ultra-processed and might be penalized by new labeling systems, even if they are currently recommended.

Physical activity attenuates the genetic predisposition to obesity associated with the FTO rs9939609 variant, effectively neutralizing the increased risk of higher BMI and subcutaneous fat area found in carriers of the risk allele.

If you carry the FTO risk gene, you are genetically predisposed to higher BMI, but this risk is not fixed. Regular physical activity and maintaining a healthy energy balance can effectively cancel out this genetic disadvantage. Do not let a genetic test result discourage you; activity is the specific counter-measure for this gene.

Among people with HIV and prediabetes, higher BMI, larger waist circumference, hypertriglyceridemia, and lower CD4 counts are associated with a significantly increased risk of progression to type 2 diabetes.

If you have HIV and prediabetes, your waist size, body weight, and triglyceride levels are strong indicators of your risk of developing full diabetes. Additionally, maintaining a higher CD4 count is protective. You should prioritize lifestyle interventions aimed at weight loss and managing triglycerides, as these are modifiable risk factors that can help prevent progression to diabetes.

Higher BMI categories (Class I-III obesity) are associated with adverse cardiometabolic profiles, including lower HDL-C, higher triglycerides, higher hsCRP, higher prevalence of hypertension and diabetes, lower physical activity (step counts), and higher mental health distress (PHQ-9/GAD-7 scores) compared to normal weight.

Maintaining a healthy weight is crucial for reducing cardiometabolic risk, but it is not the only factor. Individuals, especially those who are underweight or have obesity, should monitor blood pressure, lipids, inflammation (hsCRP), and mental health. Regular physical activity and managing stress are key components of overall health regardless of BMI category.

For middle-aged and elderly adults with type 2 diabetes, maintaining a longitudinal BMI within 18.5–26.9 kg/m² significantly reduces all-cause, cardiovascular, and cancer mortality compared to lower or higher sustained BMI levels.

If you have type 2 diabetes, aim to keep your BMI between 18.5 and 26.9 kg/m² over the long term. This range is associated with the lowest risk of death from all causes, heart disease, and cancer. Avoid sustained periods where your BMI is consistently above 27 kg/m², as this increases mortality risk.

Sustained exposure to a BMI of 27 kg/m² or higher is positively associated with increased all-cause, cardiovascular, and cancer mortality in patients with type 2 diabetes.

Keep your BMI below 27 kg/m². Sustained exposure to a BMI of 27 or higher increases your risk of dying from heart disease, cancer, or other causes. If your BMI is consistently above 27, work with your doctor to lower it gradually.

In older adults, greater leisure-time physical activity and better chair-stand physical fitness are associated with reduced leukocyte telomere length attrition over time.

For older adults, focusing on increasing leisure-time activity (like walking, gardening, or hobbies) and improving functional fitness (like the ability to stand up from a chair quickly) may help slow cellular aging. You don't need intense gym workouts; consistent, moderate leisure activity and maintaining functional strength are key metrics linked to healthier telomere dynamics.

Obesity accelerates aging and increases mortality risk in younger individuals, but the relationship between adiposity and mortality becomes non-linear and potentially protective in elderly populations, where overweight status may be associated with lower mortality than healthy weight.

If you are older, do not panic about being slightly overweight (BMI 25-30). Research suggests this range may be associated with better survival outcomes than being underweight or even 'healthy' weight in the elderly. Focus on maintaining muscle mass and metabolic health rather than aggressive weight loss, which can be detrimental in older adults.

Bariatric surgery (Roux-en-Y gastric bypass, sleeve gastrectomy, or biliopancreatic diversion) produces significantly greater body weight loss and higher remission rates of type 2 diabetes and metabolic syndrome compared to non-surgical treatment (diet, behavioral therapy, or pharmacotherapy) in individuals with a BMI ≥30, with effects sustained up to two years.

For individuals with a BMI of 30 or higher, bariatric surgery (specifically Roux-en-Y, sleeve, or biliopancreatic diversion) is significantly more effective than diet and lifestyle changes alone for losing weight and reversing type 2 diabetes. While surgery carries risks like anemia or the need for reoperation, the long-term benefits for metabolic health and weight maintenance are superior to non-surgical treatments, especially for those who have failed previous weight loss attempts.

Resistance exercise improves strength and function but does not significantly enhance weight loss or preserve fat-free mass during caloric restriction.

Include resistance training in your weight loss plan to improve your strength and daily function. However, do not expect it to stop you from losing muscle mass along with fat. You will likely lose some fat-free mass regardless of resistance training if you are in a caloric deficit. Prioritize protein intake and strength gains rather than expecting resistance training to preserve muscle mass perfectly.

Long-term metformin use (up to 10 years) produces modest but durable weight loss and waist circumference reduction in overweight/obese individuals with impaired glucose tolerance, with effects directly proportional to adherence.

If you have prediabetes or are overweight with elevated blood sugar, metformin can help you lose a modest amount of weight (about 2% of body weight) and keep it off for years. This benefit is only realized if you take the medication consistently. Start with a low dose to minimize stomach upset, which usually goes away. The weight loss comes from fat, not muscle, and works alongside lifestyle changes like diet and exercise.

Higher exercise capacity (measured in METs) is inversely and independently associated with all-cause mortality in older men (aged 65-92), with significant survival benefits achieved at capacities above 5 METs.

For older men, focusing on improving physical fitness (measured as METs) is one of the most powerful ways to extend life. You do not need to be an elite athlete; achieving a moderate fitness level (above 5 METs, roughly equivalent to brisk walking or light jogging) provides significant survival benefits. If you are currently unfit, improving your fitness through regular activity can lower your mortality risk by approximately 35% compared to staying unfit.