Browse the evidence

Smartphone calorie-tracking apps may be effective for weight loss only in patients who are already ready and motivated to self-monitor their calories.

If you are highly motivated and willing to log every meal daily, a calorie-tracking app can be a powerful tool for weight loss. However, if you find logging tedious or are too busy, the app will likely not help you lose weight. Consider your readiness for self-monitoring before relying on an app.

Waist-to-height ratio (WHtR) is the most accurate anthropometric predictor of whole-body fat percentage and visceral adipose tissue (VAT) mass compared to BMI, waist circumference, waist-to-hip ratio, and waist/height^0.5.

Measure your waist circumference and your height. Divide your waist size by your height. If the result is 0.53 or higher for men, or 0.54 or higher for women, you likely have excess body fat or visceral fat, even if your BMI says you are normal weight. This simple ratio is a better indicator of health risk than BMI or waist-to-hip ratio. Aim to keep this ratio below these thresholds to reduce cardiometabolic risk.

Specific WHtR cut-points (0.53 for men, 0.54 for women for whole-body obesity; 0.59 for visceral obesity) provide a high probability (>=0.75) of identifying individuals with high fat mass or visceral adipose tissue as measured by DXA.

Use these specific numbers to gauge your risk. If your waist-to-height ratio is 0.53 or higher (men) or 0.54 or higher (women), you likely have excess total body fat. If it is 0.59 or higher, you likely have high visceral fat, which is linked to metabolic disease. These thresholds are more accurate than BMI for identifying who needs to take action.

Long-term adherence (≥10 years) to a Mediterranean diet results in a more pronounced reduction in diabetes risk (25% reduction) compared to short-term studies.

The benefits of a Mediterranean diet for diabetes prevention accumulate over time. Maintaining this diet for at least 10 years yields a 25% lower risk compared to low adherence, suggesting that consistency is key.

Government-mandated physical isolation measures during the early COVID-19 pandemic caused a significant increase in total energy intake and snacking frequency among young adult females, while simultaneously reducing physical activity levels in both males and females.

If you are living in isolation or working from home, be aware that your default environment encourages higher calorie intake (especially snacking) and lower physical activity. To counter this, you must intentionally recreate the structure you lost: schedule your meals, limit snack availability, and deliberately schedule physical activity sessions since you no longer get incidental exercise from commuting or walking between classes.

The displacement of traditional food systems by ultra-processed products from transnational corporations increases the incidence of obesity and chronic diseases.

Protecting traditional food systems and limiting the penetration of ultra-processed products is a public health priority. Governments should enact legislation to support local farmers, stabilize prices of healthy staples, and restrict the marketing of ultra-processed foods, rather than partnering with transnational corporations.

Standard numerical nutrition labels are insufficient for accurate consumer assessment of nutrient levels, whereas the addition of interpretational aids (verbal descriptors and reference values) significantly improves the accuracy of product comparison and dietary context assessment.

When shopping, rely on labels that include simple verbal descriptors (like 'High' or 'Low' fat) and reference values (like Guideline Daily Amounts) rather than just raw numbers. These aids help you accurately compare products and understand how a single item fits into your daily diet, especially if you are older or have lower nutrition knowledge. Standard numerical-only labels are often too confusing for accurate decision-making.

Exposure to larger-sized portions, packages, or tableware consistently increases the quantity of food and non-alcoholic beverages selected and consumed by both adults and children.

To reduce food intake without willpower, reduce the size of plates, bowls, and packages you use or buy. Larger containers lead to larger servings. Switching to smaller tableware or buying smaller package sizes is a simple environmental change that reduces consumption.

Mind-body exercises such as Tai Chi and Yoga show promise for improving health-related quality of life and symptoms in fibromyalgia, potentially offering benefits comparable to or exceeding conventional exercise.

Consider incorporating Tai Chi or Yoga into your routine. Tai Chi sessions (twice weekly for 12 weeks) and Yoga (weekly supervised plus home practice) can significantly improve quality of life and symptoms. These are viable alternatives to conventional exercise.

Lifestyle physical activity interventions, such as increasing daily step counts, can improve fibromyalgia symptoms and pain levels, although long-term maintenance of these benefits may be challenging without ongoing support.

Try to increase your daily step count gradually. Using a pedometer can help track progress. While this can improve symptoms in the short term, consider combining it with structured exercise for long-term benefits.

Oral hypersensitivity to fatty acids is associated with lower habitual energy and fat intake, lower BMI, and superior ability to rank foods by fat content in human subjects.

Your ability to taste fat in food may influence how much you eat. People who are more sensitive to the taste of fat tend to eat less fat and have lower body weight. While you cannot directly 'take' sensitivity, understanding that your taste buds play a role in regulating intake might help you leverage this natural feedback loop when choosing foods.

Using a sociable robotic weight loss coach significantly increases long-term behavioral adherence (tracking duration) compared to computer-based or paper-based tracking systems, without necessarily producing superior short-term weight loss.

To stick with a weight loss plan longer, use a tool that feels socially engaging. This study suggests that a robot coach that talks to you, tracks your progress, and builds a relationship helps you keep going for months longer than a simple paper log or a silent computer program. The key is the social connection, not just the data entry.

Exercise interventions for hip or knee osteoarthritis improve self-efficacy and slightly reduce depression, but have little to no effect on anxiety.

Exercise can help boost your confidence in managing your condition and may slightly reduce depressive symptoms. However, do not expect exercise to significantly alleviate anxiety. Focus on the physical and confidence-building benefits.

Population-wide physical activity interventions, specifically pedometer programs and mass media campaigns, are dominant (cost-saving) and highly cost-effective strategies for improving public health outcomes.

To maximize health benefits and save money, prioritize low-friction, high-reach interventions. Use a pedometer to track steps (aiming for 10,000) and engage with community mass media campaigns. Avoid expensive, high-friction options like frequent travel to exercise physiologists, which offer poor value for the health outcome achieved.

A comprehensive package of six physical activity interventions (pedometers, mass media, internet, GP prescription, TravelSmart, GP referral) leads to substantial population health improvements and net cost savings for the health sector.

Implementing a mix of strategies—pedometers, media campaigns, internet resources, GP prescriptions, active transport incentives, and clinical referrals—works together to save the healthcare system money while significantly improving public health. The combined effect is greater than any single intervention alone.

Increased smartphone screen-time, particularly during the hour of and after bedtime, is associated with poorer sleep quality, reduced sleep efficiency, and longer sleep onset latency.

To improve sleep, minimize smartphone use during the hour before and after your intended bedtime. The study shows that screen time during these specific windows is linked to longer time to fall asleep and poorer sleep quality. If you must use your phone, use 'night mode' to reduce blue light, but be aware that engaging content can also stimulate your brain and delay sleep onset.

Retirement can serve as a positive transition point for increasing leisure-time physical activity, particularly moderate-intensity activities like walking, although work-related activity may decrease.

For those retiring from sedentary jobs, use the newfound time to gradually increase moderate-intensity activities like walking. Be aware that total activity might drop if you were previously physically active at work.

Daytime napping, particularly long-duration naps (>= 1 hour), is associated with an increased risk of all-cause mortality, type 2 diabetes, and chronic respiratory disease, likely serving as a marker for underlying health issues or sleep deprivation compensation.

If you find yourself needing long daytime naps (over 1 hour), view it as a signal to prioritize your nighttime sleep. Long naps are associated with higher risks of diabetes and mortality, especially in older adults. Focus on getting 7-8 hours of quality nighttime sleep rather than relying on long daytime naps to compensate.

High cost and limited accessibility of fresh fruits and vegetables are primary barriers to consumption, particularly for low-income and minority populations.

If you are on a budget, prioritize fresh produce that has a longer shelf life or buy in bulk when on sale. Recognize that cost is a systemic barrier, not just a personal failure. Look for frozen vegetables as a cost-effective, nutrient-dense alternative to fresh when fresh is too expensive or spoils too quickly.

Early home food environment and familial habits strongly predict adult fruit and vegetable consumption patterns.

If you grew up in a household with low fruit and vegetable intake, recognize that your preferences are shaped by this early environment. You can retrain your palate by experimenting with different preparation methods (e.g., roasting vs. steaming) to find flavors you enjoy, rather than relying on raw or boiled options that may have been unappealing in your childhood.

Health knowledge and awareness of benefits do not automatically translate to increased fruit and vegetable consumption due to perceived barriers.

Knowing that fruits and vegetables are healthy is not enough to change your diet if you face financial or time constraints. Focus on practical strategies to overcome these barriers, such as meal planning, buying in bulk, or choosing frozen options, rather than just reading more health information.

Regulation of meals in schools and workplaces, including bans on vending machines and provision of healthy options, shows positive short-term effects on consumption but fails to account for compensating behavior outside the intervention setting.

School and workplace healthy food programs can help, but they are not a silver bullet. If people compensate by eating less healthy food elsewhere, the net benefit is lost. These programs work best when combined with broader environmental changes that make healthy choices easy everywhere, not just at school or work.

For female migrants, higher acculturation may be associated with lower BMI due to the adoption of Western body image ideals and increased physical activity, counteracting the obesogenic food environment.

If you are a female migrant, you may find that adopting some aspects of the host culture, such as prioritizing fitness and body image, can help you maintain a healthier weight despite the availability of unhealthy foods. This doesn't mean you have to abandon your heritage; it can be a complementary strategy for health.

A structured, theory-driven group lifestyle intervention (Waste the Waist) significantly improves weight loss outcomes in high cardiovascular risk adults compared to usual care, but only when co-interventions and comorbidities are statistically controlled.

For high cardiovascular risk individuals, a structured, multi-session group program focusing on behavior change (planning, self-monitoring) is more effective for weight loss than standard brief advice, provided that other concurrent health changes are accounted for. Aim for 150 minutes of moderate activity weekly and dietary improvements.