Browse the evidence

Bariatric surgery is the most effective long-term treatment for severe obesity, significantly reducing risks of CVD, type 2 diabetes, and adverse pregnancy outcomes, yet access is inequitable due to socioeconomic and structural barriers.

If you have severe obesity and comorbidities, bariatric surgery is the most effective treatment for long-term health. Seek out high-volume centers and ensure your insurance covers the procedure and follow-up care.

A long-term intensive lifestyle intervention (caloric restriction and increased physical activity) does not significantly reduce the prevalence of electrocardiographic left ventricular hypertrophy (ECG-LVH) in overweight or obese adults with type 2 diabetes.

For individuals with type 2 diabetes and obesity, engaging in a long-term intensive lifestyle intervention (diet and exercise) is unlikely to reverse electrocardiographic signs of left ventricular hypertrophy, even if it helps maintain weight loss. While lifestyle changes are crucial for overall health, patients should not expect this specific cardiac structural improvement as a guaranteed outcome of modest weight loss.

Global obesity prevalence has increased significantly and now exceeds underweight prevalence in the vast majority of countries, creating a 'double burden' of malnutrition driven by rising obesity rather than persistent undernutrition.

Focus on healthy nutrition transitions that enhance access to nutritious foods. Address the remaining burden of underweight while curbing and reversing the increase in obesity.

Classically activated (M1) macrophages reprogram their metabolism to favor aerobic glycolysis and lactate production over oxidative phosphorylation, leading to TCA cycle interruptions and accumulation of metabolites like citrate and succinate.

When immune cells fight acute threats, they switch to a fast, inefficient energy mode (glycolysis) that produces lactate and specific metabolites. This metabolic shift is a key part of the inflammatory response.

Calorie restriction (energy deficit) is the primary driver of weight loss, with macronutrient composition having a secondary or negligible impact on long-term outcomes.

To lose weight, you must consume fewer calories than you burn. The specific type of diet (low-carb, low-fat, etc.) matters less for long-term success than maintaining that calorie deficit. Choose a dietary pattern you can sustain that creates this deficit.

Reducing dietary energy density (consuming larger portions of lower-calorie foods) improves satiety and aids weight loss maintenance, regardless of total caloric intake in the short term.

To make your diet easier to stick to, choose foods that are less energy-dense. This means eating more vegetables, fruits, and lean proteins relative to fats and sugars. You can eat larger portions of these foods, which helps you feel fuller for longer, making it easier to maintain a calorie deficit without feeling deprived.

Increasing physical activity (specifically total, light, and moderate-to-vigorous activity) or decreasing sedentary time during a dietary energy restriction intervention is associated with a faster rate of weight loss in women with overweight and obesity.

If you are on a calorie-restricted diet to lose weight, try to stay active or increase your daily movement. This paper shows that people who increased their physical activity (even light activity) or reduced their sitting time lost weight faster than those who became more sedentary. You don't need to start a rigorous gym routine; simply maintaining or slightly increasing your daily steps and reducing sedentary time can help you reach your goal sooner.

Increases in total and moderate-to-vigorous physical activity (MVPA) during the post-weight loss maintenance phase are associated with less weight regain (or greater weight loss) one year after the intervention.

After you reach your weight loss goal, don't stop moving. This study found that people who kept up or increased their moderate-to-vigorous exercise (like brisk walking or jogging) after losing weight were much more likely to keep it off one year later. Treat your post-goal activity as a permanent part of your lifestyle, not just a tool for getting to the goal.

Caloric restriction is the primary and most effective method for weight loss in obesity treatment, regardless of macronutrient composition.

To lose weight effectively, focus on reducing your total daily calories rather than obsessing over specific macronutrient ratios. Aim for a daily intake of approximately 25 kcal per kg of your standard body weight. If you have severe obesity (BMI ≥ 35), start with 20-25 kcal/kg. A modest weight loss of 3-5% of your current body weight is sufficient to improve health risks like high blood pressure and blood sugar. Combine this with behavioral changes like self-monitoring and adequate protein intake to preserve muscle mass.

Aerobic physical activity (30-60 minutes, moderate to vigorous intensity, most days) improves cardiometabolic risk factors and reduces visceral fat, even without significant weight loss.

Aim for 30-60 minutes of moderate to vigorous aerobic exercise most days of the week. This will reduce dangerous visceral fat and improve your blood pressure and blood sugar, even if you don't lose much weight on the scale.

Moderate intensity physical activity (150-250 min/week) prevents weight gain, while >250 min/week is required for weight maintenance after loss.

To keep weight off, aim for more than 250 minutes of moderate exercise per week. To prevent gaining weight, 150-250 minutes is sufficient. Do not rely on exercise alone for weight loss; combine it with dietary changes.

Weight loss of 3-10% of baseline body weight reduces systolic and diastolic blood pressure by approximately 3 mmHg, independent of salt restriction, primarily through decreased sympathetic nervous system activity and improved insulin sensitivity.

If you have high blood pressure and are overweight, aim to lose just 3-10% of your current body weight. You do not need to reach a 'perfect' weight to see benefits; this modest loss can lower blood pressure by about 3 mmHg. Work with a dietitian to achieve this gradually using calorie reduction and behavioral strategies like appetite awareness, rather than crash dieting.

Regular physical activity, including aerobic, dynamic resistance, and isometric training, reduces blood pressure, with isometric training showing significant reductions when performed at ~30% of maximal voluntary contraction.

Engage in 150-300 minutes of moderate aerobic activity (like brisk walking) or 75-150 minutes of vigorous activity weekly. Add resistance training twice a week. If you have limited time or equipment, try isometric exercises (like wall sits or handgrips) at about 30% of your maximum effort. The key is consistency and reducing sedentary time.

Consumption of ultra-processed foods (UPFs) causes increased energy intake and weight gain compared to whole foods, independent of matched macronutrients.

Prioritize whole, minimally processed foods. Even if you match the calories and macros, ultra-processed foods are engineered to override your body's natural fullness signals, leading you to eat significantly more and gain weight.

A long-term intensive lifestyle intervention (ILI) focused on weight loss and physical activity significantly reduces the symptoms of diabetic peripheral neuropathy (DPN) in overweight or obese adults with type 2 diabetes, as measured by the Michigan Neuropathy Screening Instrument (MNSI) questionnaire.

For individuals with type 2 diabetes and excess weight, achieving and maintaining weight loss through diet and exercise can significantly reduce the symptoms of nerve pain and numbness associated with diabetic neuropathy. The benefits are linked to the amount of weight lost, suggesting that even modest, sustained weight loss efforts can protect nerve health over the long term.

Female athletes should maintain an energy availability of 40–45 kcal/kg fat-free mass per day to sustain eumenorrhea, bone health, and metabolic function, as habitual low energy availability leads to Relative Energy Deficiency in Sport (RED-S) or the Female Athlete Triad.

Calculate your daily energy needs by adding your basal metabolic rate to the energy cost of your exercise. Ensure the remaining calories (Energy Availability) are at least 40-45 kcal per kg of fat-free mass. If you are skipping meals or restricting calories to lose weight, you risk losing your period and bone density. Prioritize fueling your training to support your body's structural integrity.

Intensive lifestyle interventions, such as the Look AHEAD program, can produce significant long-term weight loss (6%) in people with type 2 diabetes, and are generally cost-effective compared to population obesity trends.

For individuals with severe obesity and type 2 diabetes, intensive lifestyle interventions like the Look AHEAD program can lead to significant long-term weight loss (6%) and are cost-effective. Consistency and intensity are key.

High-intensity interval training (HIT) performed 3 times per week for approximately 15 minutes total induces rapid improvements in cardiovascular fitness, skeletal muscle mitochondrial density, and insulin sensitivity in previously untrained individuals.

If you are new to exercise or short on time, try High-Intensity Interval Training (HIT). Perform 4-10 bouts of 30 seconds to 4 minutes of intense effort, with 1-3 minutes of rest in between, 3 times a week. This totals about 15 minutes of intense work and can rapidly improve your fitness and insulin sensitivity.

Low-load (30% 1RM) high-volume resistance exercise until volitional failure stimulates muscle protein synthesis at rates similar to high-load (90% 1RM) exercise, making it suitable for maintaining lean mass in previously untrained and elderly individuals.

If you are elderly or new to resistance training, you can maintain muscle mass by performing low-load exercises (using bodyweight or light bands) until you reach muscle failure. Combine this with a daily protein intake of 1.2 g/kg body weight for best results.

Combined aerobic interval training (AIT) and weight loss via low-energy diet (LED) produces superior body composition improvements (weight, fat mass, waist circumference) compared to AIT alone in overweight CAD patients, while both interventions yield similar improvements in VO2peak and lipid profiles.

For overweight CAD patients, combining aerobic interval training with a short-term, supervised low-energy diet yields significantly better fat loss and waist reduction than exercise alone. Both approaches improve heart health (VO2peak, lipids), but adding a calorie-restricted diet is crucial for body composition goals.

Achieving a minimum of 60 highly active minutes per week is a significant predictor of clinically significant weight loss (≥5% baseline weight).

Aim for at least 60 minutes of high-intensity activity per week. This can be broken into short bursts. This level of activity is a strong predictor of reaching a 5% weight loss goal.

Maintaining a daily step count of 5000 or more is a significant predictor of clinically significant weight loss (≥5% baseline weight).

Aim for at least 5,000 steps per day. This is a significant predictor of reaching a 5% weight loss goal. Higher steps (up to 10k+) correlate with even greater loss, but 5k is a solid starting point.

Post-diagnosis weight loss of more than 1% per year is associated with a decreased risk of microvascular complications (kidney disease and neuropathy) compared to stable weight.

If you have Type 2 Diabetes, achieving a modest weight loss of just over 1% of your body weight per year after diagnosis can significantly lower your risk of kidney and nerve damage. This does not require extreme dieting; small, consistent changes are effective.

Intentional weight loss, particularly through bariatric surgery, significantly reduces the risk of hospitalization and ICU admission for patients with severe obesity who contract COVID-19.

For individuals with severe obesity, bariatric surgery can lead to significant weight loss and a substantially lower risk of severe COVID-19 outcomes, including hospitalization and ICU admission. While surgery is a major decision, it should be considered as a viable option for those who meet the criteria, as it can offer substantial health benefits beyond weight loss.