Browse the evidence

Intermittent energy restriction (IER) involving 2-3 fasting days per week produces greater short-term absolute weight loss and percentage of weight loss compared to continuous energy restriction (CER) when total energy deficit is matched.

If you struggle with daily calorie counting, try restricting calories to 400-600 kcal on 2-3 days a week (fasting days) and eating normally on the other days. This method may help you lose more weight in the short term (under 6 months) than eating slightly less every day, provided your total weekly calories are similar to the daily restriction approach.

A structured weight management program using Total Diet Replacement (TDR) with a hypocaloric formula diet (approx. 850 kcal/day) for 3-5 months induces significant weight loss and Type 2 Diabetes (T2D) remission in South Asian populations, comparable to outcomes in white European cohorts.

For South Asians with recent Type 2 Diabetes, a strict, short-term (3-5 month) program using a ~850 kcal/day formula diet can reverse the disease. This involves replacing all food with formula, stopping diabetes meds under supervision, and then slowly reintroducing real food. It works similarly for South Asians as it does for white Europeans, primarily by reducing liver fat through significant weight loss.

Combining time-restricted eating (TRE) with calorie restriction (CR) significantly reduces body weight, fat mass, and waist circumference compared to calorie restriction alone in overweight or obese adults.

If you are overweight or obese, combining a moderate calorie deficit with time-restricted eating (eating within a specific window of the day) will help you lose more weight and fat than just counting calories alone. However, do not expect this combination to significantly improve your blood pressure, blood sugar, or cholesterol levels beyond what you would get from calorie restriction alone.

Intermittent fasting 5:2 plus (30% energy on 2 fasting days, 70% on 5 non-fasting days) produces superior short-term weight loss compared to daily calorie restriction (70% energy daily) in Chinese adults with overweight or obesity.

If you have overweight or obesity, try an Intermittent Fasting 5:2 Plus program for 12 weeks. Eat about 30% of your normal calories on 2 non-consecutive days a week, and 70% on the other 5 days. Combine this with 150-300 minutes of moderate exercise weekly and behavioral tips like self-weighing. This approach led to significantly more weight loss than eating 70% of your calories every day in this study.

Intermittent fasting during Ramadan leads to significant reductions in body weight, BMI, fat mass, and waist circumference in healthy young men, primarily driven by negative energy balance.

If you fast from sunrise to sunset for a month, you will likely lose weight and body fat, provided you don't overeat during non-fasting hours. This study showed a modest but significant drop in weight and fat mass, driven by eating less overall.

Very Low Calorie Diet (VLCD) is highly effective for weight loss, producing a mean difference of -4.50 kg compared to eucaloric diet.

VLCD is a highly effective intervention for weight loss, producing a mean loss of 4.5 kg more than eucaloric diet. It should be undertaken with medical supervision due to its intensity.

A hybrid digital health weight loss program combining a mobile application, wireless scale, and meal replacement biscuits achieves clinically significant short- and midterm weight loss (average 5.4 kg at 120 days) without face-to-face interaction.

To lose weight using this method, you need a smartphone, a compatible wireless scale, and access to the specific meal replacement biscuits (Yufit) recommended by the MetaWell app. The core mechanism is a caloric deficit achieved by replacing some meals with these low-calorie biscuits (up to 3 daily) while following the app's personalized meal plan. You must weigh yourself daily using the scale and log it in the app. The program is designed to be remote, so you do not need to see a doctor or nutritionist in person. If your BMI drops below 22, the program switches to maintenance mode.

A remote digital health intervention combining mobile applications, wireless scales, and low-calorie meal replacement biscuits produces clinically significant weight loss (mean 14 kg, 13% total body weight loss) in severely obese individuals (BMI ≥35 kg/m2) over 120 days.

If you have severe obesity (BMI ≥35), a structured digital program using meal replacement biscuits and daily self-weighing can lead to significant weight loss (around 13% of body weight over 4 months). The key is consistency: weigh yourself daily using a connected scale and follow the prescribed meal plan. This approach is designed to be accessible and scalable, offering a viable alternative to more invasive or expensive treatments for those who can adhere to the protocol.

A 28-day low-calorie diet (800–1100 kcal/day) induces a linear reduction in hepatic fat content and rapid, time-dependent improvements in hepatic insulin sensitivity and lipid metabolism in obese women.

For obese women, a strict 28-day low-calorie diet (800-1100 kcal) significantly reduces liver fat by over 50% and rapidly improves insulin sensitivity within the first week. While metabolic markers like ketones and liver enzymes (ALT) may rise temporarily due to increased fat burning, this is part of the adaptive process. The key is sustained caloric restriction, which yields linear liver fat loss and metabolic health gains.

Intensive diet-induced weight loss (approx. 13.4% body weight over 12 weeks) leads to rapid and complete resolution of hepatic steatosis in NAFLD patients, with 90% achieving complete resolution as measured by MRI.

For NAFLD patients, a 12-week intensive meal replacement program (approx. 1100 kcal/day) can completely resolve liver fat in 90% of cases. This rapid resolution is achievable even with Class II obesity, suggesting that short-term intensive intervention is a viable and effective primary treatment strategy.

Time-restricted eating (TRE) without calorie restriction significantly reduces body weight, BMI, and whole-body fat mass in adults.

Adopt a 16:8 eating window (e.g., 12pm-8pm) for daily food intake. Do not restrict calories intentionally; simply stop eating after your chosen window. Expect modest weight loss (~1.6kg) and fat reduction over time, especially if you have metabolic risk factors.

Preoperative dietitian-led Very Low Calorie Diet (VLCD) of 800-1000 kcal/day for 2-12 weeks significantly reduces weight and waist circumference in obese adults undergoing elective surgery without causing unfavorable lean body mass loss.

If you are scheduled for elective surgery and have obesity, ask your surgeon or care team about a preoperative dietitian-led Very Low Calorie Diet (VLCD). This involves consuming 800-1000 calories daily, primarily through meal replacements, for 2-12 weeks before your operation. Crucially, a dietitian must monitor your protein intake to ensure you do not lose muscle mass, which can complicate surgery and recovery. This approach has been shown to significantly reduce weight and waist circumference, potentially making the surgery technically easier and reducing complications.

A 16-week Tabata training program significantly reduces body fat percentage, fat mass, BMI, and waist circumference in healthy inactive women.

If you are a healthy woman with a sedentary job, performing Tabata-style high-intensity intervals (20 seconds hard work, 10 seconds rest) for about 20 minutes, 4 times a week, for 4 months, can significantly reduce your body fat and waist size without needing to change your diet drastically.

HIIT is more time-efficient than MICT for achieving similar fat loss outcomes, primarily due to excess post-exercise oxygen consumption (EPOC) and appetite regulation.

If you are short on time, HIIT can provide similar fat loss benefits to longer cardio sessions in less time, thanks to increased calorie burn after exercise.

Very Low Calorie Diet (VLCD) is a highly effective intervention for weight loss, ranking highest in its network.

A Very Low Calorie Diet (VLCD) produces significant weight loss (approx. 4.5 kg more than maintenance) compared to eucaloric diets. It was the top-ranked treatment in its network, suggesting high efficacy for rapid weight reduction under medical supervision.

Combining calorie restriction with exercise (Hyc+Ex) is more effective than exercise alone.

Combining calorie restriction with exercise is more effective for weight loss than exercise alone. This combination was the top-ranked treatment in its network, producing a mean weight loss of 4.45 kg.

A structured exercise program combined with nutritional education significantly increases physical activity levels, energy expenditure, and reduces anthropometric obesity markers (weight, BMI, waist circumference) in obese sedentary workers.

If you have a sedentary job, combine 3 hours of moderate-to-high intensity structured exercise per week (like jogging, gym, or sports) with a diet low in calories but high in fiber and vitamins. Additionally, increase your daily spontaneous movement by taking stairs and walking more. This combined approach significantly reduces weight and waist circumference in obese workers.

Intermittent fasting (5:2 diet) produces significantly greater weight loss and improvements in insulin resistance compared to continuous calorie restriction in overweight women over 12 weeks.

If you are overweight and non-diabetic, try a 5:2 intermittent fasting schedule for 12 weeks. On two non-consecutive days, eat only 20-25% of your daily energy needs. On the other five days, eat normally. This approach may lead to greater weight loss and better insulin sensitivity than simply cutting calories every day.

A structured 12-week calorie-restricted dietary intervention starting with a 6-week Very Low-Calorie Diet (VLCD) phase (800-1200 kcal/day) followed by a 6-week maintenance phase significantly reduces body weight and improves postprandial glycemic response in Korean adults with early type 2 diabetes and obesity.

For Korean adults with early type 2 diabetes and obesity, a structured 12-week program starting with a 6-week very low-calorie diet (800-1200 kcal/day, with meals provided) followed by a 6-week self-managed maintenance phase can lead to significant weight loss (approx. 7-8%) and improved blood sugar control. The key is the structured, phased approach and meal provision to ensure adherence.

Nutritional guidance that dynamically adjusts energy intake based on regular measurements of Resting Energy Expenditure (REE) and physical activity effectively reduces body weight in patients with obesity without triggering metabolic adaptation (REE reduction) or increasing hunger.

To lose weight without triggering your body's survival mechanisms (slowed metabolism and intense hunger), you must tailor your calorie intake to your specific energy burn. This involves measuring your Resting Energy Expenditure (REE) and tracking physical activity, then adjusting your daily calorie target regularly (e.g., weekly) as your body changes. Use technology like meal-tracking apps to ensure you are hitting these dynamic targets. This personalized approach allows for significant weight loss (approx. 5% in 24 weeks) while keeping your metabolism and hunger levels stable.

Both 5:2 and 16:8 intermittent fasting protocols produce statistically significant weight loss in overweight and obese individuals over a 6-week period, with no statistically significant difference in efficacy between the two methods.

If you are overweight or obese, you can choose either the 5:2 method (eating very little on 2 days a week) or the 16:8 method (eating within an 8-hour window daily) to lose weight. Both work significantly over 6 weeks, and neither is proven to be better than the other. Pick the one you can stick with consistently.

Structured calorie-restricted diets (800-1,800 kcal) can induce diabetes remission in obese Korean adults with early-onset Type 2 Diabetes, with remission rates up to 75%.

If you have recently been diagnosed with Type 2 Diabetes and are obese, a structured diet starting at 800 calories and moving to 1,200-1,800 calories can potentially put your diabetes into remission, especially if you stop other medications under doctor supervision.

Both volumetric dieting (energy density ≤ 1.5 kcal/g) and time-restricted eating (8-hour window) produce equivalent reductions in body weight and fat mass while preserving lean body mass in middle-aged, physically active adults over 12 weeks.

If you want to lose fat and keep muscle without changing your exercise routine, you can choose either to eat lower-energy-density foods (more volume, fewer calories per gram) or to eat all your calories within an 8-hour window. Both methods worked equally well in this study. Choose the one you can stick to consistently, as adherence was higher for the time-restricted eating group.

Intermittent severe caloric restriction (3 days/week, 600-800 kcal) combined with habitual intake on other days for 6 weeks produces significant weight loss primarily from android fat mass while preserving fat-free mass and maintaining metabolic health in active athletes.

If you are an active athlete needing to lose weight, try restricting calories to 600-800 kcal on 3 alternating days (e.g., Mon/Wed/Fri) while eating normally on the other 4 days for 6 weeks. This method preserves muscle better than daily dieting and is easier to stick to socially. Ensure you are eating enough protein on non-restriction days to support your training.