Browse the evidence

In overweight or obese patients with type 2 diabetes, each kilogram of weight loss achieved through non-surgical interventions (diet or pharmacotherapy) results in a mean reduction of 0.1 percentage points in glycated hemoglobin (HbA1c).

For every kilogram (2.2 lbs) of body weight you lose, your HbA1c is expected to drop by 0.1 percentage points. This applies to overweight or obese adults with Type 2 Diabetes using diet or non-surgical drugs. The benefit is linear: more weight loss equals more HbA1c reduction. This holds true regardless of whether you use low-carb, low-fat, or pharmacological weight loss strategies, as long as weight is lost. Note: This model applies to non-surgical interventions over 3-24 months.

High levels of physical activity preserve mitochondrial capacity and exercise efficiency in older adults, effectively negating the negative impacts of chronological aging on these metrics.

If you are an older adult, maintaining a high level of physical activity, particularly endurance exercise, is crucial for preserving mitochondrial health. This preservation directly supports better muscle quality, exercise efficiency, and physical performance, effectively counteracting many negative effects typically associated with aging. Focus on staying active rather than accepting decline as inevitable.

An estimated average protein requirement of 0.66 g/kg body weight per day of good-quality protein is probable for healthy adults, with a recommended dietary allowance (RDA) of 0.83 g/kg/day established via nitrogen balance studies.

For most healthy adults, aiming for 0.83 grams of high-quality protein per kilogram of body weight daily is sufficient to meet nutritional requirements. You do not need to consume excessive amounts of protein for basic health maintenance.

Empagliflozin (10 mg/day) leads to significant reductions in body weight and visceral adipose tissue (VAT) area in patients with T2DM and NAFLD, whereas pioglitazone increases these metrics.

Empagliflozin (10 mg daily) not only helps control blood sugar but also significantly reduces body weight and visceral fat in patients with Type 2 Diabetes and fatty liver disease. This is in contrast to pioglitazone, which tends to increase weight and fat. This weight loss benefit supports liver health improvement.

High-intensity resistance training increases energy requirements and resting metabolic rate in older adults, facilitating body fat loss and maintenance of metabolically active tissue.

For older adults looking to manage body fat, resistance training is effective because it increases your resting metabolic rate and the energy you burn during exercise. This means you can eat more (about 15% more in the study) while maintaining your weight, making it easier to sustain a healthy diet without feeling deprived.

Lifestyle modifications, specifically diet, physical exercise, and weight loss, are the primary effective therapeutic interventions for Non-Alcoholic Fatty Liver Disease (NAFLD) and Metabolic Syndrome (MS), as they directly improve insulin resistance and histological liver outcomes.

To treat fatty liver, you must change your lifestyle. There are no approved drugs that work as well as losing weight and moving more. Aim for a 7-10% reduction in body weight through a healthy diet (like the Mediterranean diet) and regular physical activity. This improves insulin resistance and reduces liver fat and inflammation.

Incorporating 1-2 meal replacements per day into a traditional lifestyle intervention significantly increases weight loss compared to traditional lifestyle intervention alone in overweight premenopausal women.

To lose more weight, replace 1-2 of your main meals daily with a nutritionally complete meal replacement shake or bar (approx. 220 kcal). Combine this with a daily goal of walking 10,000 steps and following a 1200-calorie diet plan. This structured approach has been shown to nearly double weight loss compared to diet and exercise alone in overweight women.

Weight loss of 5-10% of initial body weight significantly reduces chronic disease risk factors (body fat, BMI, waist circumference, resting energy expenditure, insulin, cholesterol, LDL), while weight loss of 10% or greater provides additional significant improvements in blood pressure and triglycerides.

Aiming for a 5-10% reduction in your initial body weight can significantly improve your cholesterol, blood sugar, and blood pressure. If you can achieve 10% or more, you may see additional improvements in blood pressure and triglycerides. Focus on steady, sustainable weight loss rather than rapid, extreme measures.

Low Energy Availability (LEA), defined as energy availability < 30 kcal/kg fat-free mass (FFM) per day, causes detrimental physiological adaptations including endocrine suppression, reduced bone mineral density, and impaired performance in both male and female athletes.

Ensure your daily energy intake minus exercise expenditure is at least 30 kcal per kg of fat-free mass. If you are an athlete, especially in weight-sensitive sports, monitor for signs of LEA such as fatigue, menstrual irregularities (in females), or decreased performance. Consult with sports dietitians and medical professionals to adjust nutrition and training loads appropriately.

Intentional weight loss via caloric restriction in obese elderly individuals with mild cognitive impairment (MCI) is associated with improvements in global cognition, verbal memory, executive function, and language.

If you are an older adult with obesity and mild memory issues, working with a nutritionist to create a moderate calorie deficit (around 500 calories less per day) can help improve your thinking skills and memory. This approach is safe and does not necessarily cause muscle loss if you maintain your usual physical activity levels.

Preventing weight gain requires only small, sustainable changes in energy balance (approximately 100 kcal/day), whereas treating established obesity requires large, difficult-to-sustain behavior changes that trigger strong physiological compensation.

To stop gaining weight, you don't need a drastic diet or intense gym sessions. Aim for a modest daily deficit of about 100 calories. This can be achieved by walking 2,000 extra steps a day and eating 100 calories less. These small, sustainable changes are easier to maintain than strict diets and are effective for preventing weight gain in the vast majority of adults.

Caloric restriction induces a metabolic adaptation (reduction in energy expenditure greater than expected from loss of fat-free and fat mass) and a behavioral adaptation (reduction in physical activity) that together reduce total daily energy expenditure, thereby creating resistance to further weight loss and promoting weight regain.

When you restrict calories, your body fights back by lowering your resting metabolism and making you move less (fidgeting, posture, steps). This is a biological survival mechanism, not a personal failure. To maintain weight loss, you must account for this drop in energy expenditure. Combining diet with exercise may help prevent this metabolic slowdown, but you must also be aware that your natural daily activity levels may drop unconsciously as you lose weight.

Very Low-Energy Diets (VLEDs, <800 kcal/d) produce significantly greater short-term weight loss than Low-Energy Diets (LEDs, 800-1800 kcal/d), but this advantage diminishes and becomes statistically non-significant after 12 months.

If you need rapid weight loss (e.g., for surgery or diabetes remission), a medically supervised Very Low-Energy Diet (<800 kcal) works faster than standard diets. However, do not expect this advantage to last beyond a year. The key is using VLED as a short-term tool (12-20 weeks) to achieve a significant initial loss, then carefully transitioning to a sustainable maintenance diet to keep the weight off.

Dietary intervention alone is superior to exercise intervention alone for long-term reduction of body weight and fat mass in overweight/obese individuals.

If you can only choose one lever for long-term weight loss, choose diet. This study shows that dietary changes alone lead to significantly more weight and fat loss than exercise alone. While exercise is crucial for cardiovascular health and preserving muscle, diet is the primary driver of scale weight reduction. Focus on sustainable caloric restriction first.

Increasing consumption of whole, fresh fruit promotes weight maintenance or modest weight loss and does not contribute to excess energy intake or adiposity.

You do not need to fear fruit for weight loss. Eating more whole, fresh fruit is likely to help you maintain your weight or lose a small amount of weight, rather than causing gain. Focus on whole fruits (apples, berries, etc.) rather than juices or dried fruits, as the fiber and water content help you feel full without consuming excess calories.

Ultraprocessed food consumption is a primary driver of obesity due to high energy density, low satiety, and ease of overconsumption.

Reduce your intake of ultraprocessed foods (high in fats, sugars, and energy density). Focus on whole foods like fruits, vegetables, and grains to manage portion sizes and energy intake more effectively.

Long-term caloric restriction (12 months) induces metabolic adaptation (Total Energy Expenditure lower than predicted by body composition changes), regardless of whether the diet is High or Low Glycemic Load.

When you lose weight, your body naturally burns fewer calories than expected for your new size. This 'metabolic adaptation' happens whether you eat high or low glycemic carbs. It is a normal survival mechanism, not a broken metabolism. To counteract it, focus on preserving muscle mass (which LG diets may help with) and maintaining your weight loss, as the adaptation is a risk factor for weight regain.

After 24 months of adherence, there is no significant difference in weight loss or improvements in metabolic risk factors between low-carbohydrate diets and low-fat diets.

If you can stick to either a low-carb or low-fat diet for 2 years or more, you will likely achieve similar weight loss and metabolic improvements. The initial advantages of one over the other fade over time, so choose the one that fits your lifestyle and preferences best.

In crossover diet studies without washout periods, the order of macronutrient manipulation (specifically Low Carbohydrate vs. Low Fat) significantly affects energy balance and body composition outcomes due to carryover effects from gut adaptations.

If you are designing or interpreting a nutrition study that switches between two diets without a break, the order matters. Starting with a high-volume, high-fiber diet (like a Low Carb diet in this study) before switching to a lower-volume diet can lead to significantly greater weight loss than the reverse order, likely because the gut adapts to the volume/fiber of the first diet, reducing intake in the second. For individuals, this suggests that the sequence of dietary changes might impact long-term adherence and results, though this specific mechanism (gut adaptation to mass) is most relevant in controlled settings.

Fat-free mass (FFM) is the primary determinant of 24-hour energy expenditure, explaining 81% of the variance between individuals, while spontaneous physical activity (fidgeting) accounts for significant residual variability (100-800 kcal/d) independent of body size.

Your daily energy needs are mostly determined by your lean muscle mass, but your daily habits of movement (fidgeting, pacing, general activity) significantly alter that number. Two people with the same weight and muscle mass can have vastly different calorie burn rates simply based on how much they move spontaneously throughout the day. Do not rely on static 'one-size-fits-all' calorie targets; adjust for your actual daily activity levels.

Medical nutrition therapy (MNT) provided by a registered dietitian is effective for improving weight outcomes and metabolic markers, but should not be used in isolation due to compensatory brain mechanisms.

Work with a registered dietitian for personalized nutrition advice. Do not rely on diet alone; combine it with physical activity and psychological support to manage the biological drive to regain weight.

A 25% caloric deficit induces mitochondrial biogenesis (increased mtDNA content and expression of biogenesis genes like PPARGC1A and SIRT1) in human skeletal muscle, leading to improved metabolic efficiency and reduced oxidative stress without increasing the activity of key mitochondrial enzymes.

If you are overweight but not obese, a sustained 25% reduction in calories for several months can reprogram your muscle cells to become more energy-efficient. This involves creating more mitochondria (the power plants of your cells) and upregulating specific genes (like SIRT1 and PGC-1alpha) that manage energy. Interestingly, this happens without necessarily increasing the speed at which your muscles burn fuel (enzyme activity), suggesting your body is becoming more 'efficient' rather than just 'faster'. This adaptation may help reduce oxidative stress and DNA damage associated with aging.

Ad libitum low-fat diets produce a statistically significant, dose-dependent weight loss in overweight individuals without requiring active energy restriction.

To lose weight without counting calories, reduce the percentage of your daily energy coming from fat. This meta-analysis shows that simply lowering fat intake (while eating ad libitum) leads to an average loss of about 2.5 kg in overweight individuals over several months. The key is that low-fat foods are less energy-dense, which naturally reduces total calorie intake.

The magnitude of weight loss on a low-fat diet is positively correlated with initial body weight and the percentage reduction in dietary fat.

If you are overweight, lowering your fat intake will result in more weight loss than if you were normal weight. Specifically, for every 1% you reduce the percentage of calories from fat, you can expect to lose an additional 0.37 kg over the study period.