Browse the evidence

Intentional weight loss, particularly through bariatric surgery, is associated with improvements in New York Heart Association (NYHA) classification, diastolic function, and reductions in left ventricular (LV) mass index and left atrial size.

Intentional weight loss improves heart function, including diastolic function and reducing left ventricular mass and left atrial size.

Very Low Calorie Diets (VLCD) produce substantial short-term weight loss (10-17 kg) but suffer from gradual attenuation and weight regain over time unless supported by behavioral interventions.

VLCDs are powerful for rapid short-term loss but require medical supervision and a structured reintroduction phase. Without behavioral support, the weight loss is likely to be partially regained over time.

Intermittent Energy Restriction (IER) strategies (TRE, PF, ADF) produce short-term weight loss comparable to Continuous Energy Restriction (CR), with no significant long-term difference between the two approaches.

Choose an IER method (like Time-Restricted Eating) if it helps you adhere to your calorie goals, but do not expect it to be more effective than continuous calorie restriction in the long run. The key is consistency and adherence.

In middle-aged and older adults, weight gain is associated with an increased risk of atherosclerosis (measured by cIMT > 1.0 mm), particularly in those under 65, those with prior cardiovascular events, and those who are overweight or obese at baseline.

For adults over 45, gaining weight is a clear risk factor for developing atherosclerosis, especially if you are already overweight, obese, or have had heart issues. Focus on maintaining a stable, healthy weight rather than chasing rapid weight loss, which may not improve arterial health markers in this age group.

BMI mediates the association between macronutrient quality and phenotypic age acceleration, accounting for approximately 20-30% of the effect.

Dietary changes slow aging partly by helping you maintain a healthy weight. If you are trying to slow biological aging, combining high-quality food choices with weight management strategies will be more effective than diet alone.

Consumption of sugar-sweetened beverages (SSBs) is positively associated with increased waist circumference and BMI in diabetic patients, independent of other dietary factors.

Reduce or eliminate sugar-sweetened beverages to help manage waist circumference and BMI. This is a key dietary modification for diabetic patients.

Mediterranean and low-carbohydrate diets combined with exercise reduce cardiovascular and metabolic risk factors in prostate cancer patients undergoing androgen deprivation therapy (ADT).

If you are undergoing hormone therapy for prostate cancer, adopting a Mediterranean or low-carbohydrate diet alongside regular exercise can help manage metabolic risks like weight gain and blood sugar issues. While the benefits are clear, sticking to these changes long-term can be challenging, so focus on consistency over perfection.

Targeting thermogenesis via β3-adrenergic receptor (β3-AR) activation can increase energy expenditure and promote brown adipose tissue (BAT) activity, offering a complementary mechanism to GLP-1 agonists for obesity management.

Research is actively exploring medications that activate brown fat (thermogenesis) to burn more calories. While not yet standard care, these drugs (like β3-agonists) work by increasing energy expenditure. They may eventually be used alongside GLP-1 medications to overcome weight loss plateaus. Current options are limited by side effects, but newer, more selective drugs are showing promise in clinical trials.

Frequent consumption of beer (a few times per week) and sweets (once a week or more) is associated with an increase in body fat percentage and a decrease in skeletal muscle mass in older adults.

For older adults, drinking beer a few times a week and eating sweets weekly or more is linked to higher body fat and lower muscle mass. Reducing the frequency of these items may help maintain body composition.

Tirzepatide, a dual GLP-1/GIP agonist, may enhance metabolic efficiency and endurance performance by optimizing fat oxidation, delaying glycogen depletion, and improving mitochondrial function.

If you are an endurance athlete using tirzepatide, you may experience improved metabolic efficiency. The drug can help spare glycogen stores and enhance mitochondrial function, potentially supporting longer exercise durations. However, monitor for signs of hypoglycemia during high-intensity training and ensure adequate carbohydrate intake to counteract potential energy deficits.

In individuals with MASLD undergoing ~30% caloric restriction, resistance training preserves skeletal muscle mass and improves functional strength, whereas adding whey protein supplementation (1.5 g/kg/day) provides no additional benefit over resistance training alone (0.8 g/kg/day).

If you have MASLD and are cutting calories significantly, focus on resistance training and getting adequate protein (around 0.8 g/kg/day). Adding extra whey protein (up to 1.5 g/kg/day) does not provide extra muscle or strength benefits in this specific scenario. The energy deficit blunts the potential synergy of high protein and exercise.

Transitioning from non-obese to obese status or maintaining obesity significantly increases the risk of MASLD, with risk escalating with age and magnitude of weight gain.

Gaining weight, especially transitioning from a normal weight to obese, drastically increases your risk of fatty liver disease. The more weight you gain (especially >20kg), the higher the risk. Maintaining a stable, non-obese weight is the most protective strategy.

The reduction in energy intake from lower energy density meals is linearly related to the change in energy density, with stronger effects in adults than children and in entrée designs compared to preloads.

The calorie-reducing effect of low energy density foods is strongest in adults and when consumed as main meals (entrées). In children, the effect is smaller, and preloads may be less effective than main meals.

Intermittent fasting (IF) produces a statistically significant greater reduction in Body Mass Index (BMI) compared to continuous energy restriction (ER), although the absolute difference in total body weight loss is not statistically significant.

If you are trying to lose weight, intermittent fasting may help you reduce your BMI slightly more than just counting calories every day, even if the scale doesn't move much faster. Try a 16:8 schedule (fast for 16 hours, eat within 8 hours) or alternate-day fasting. Be aware that you might feel dizzy, while those just cutting calories might get more headaches. The key is consistency with whichever method you choose.

Intermittent fasting and continuous energy restriction produce similar improvements in blood pressure (systolic and diastolic), LDL cholesterol, and HDL cholesterol, with no statistically significant differences between the two methods.

If your goal is to lower blood pressure or improve cholesterol, you do not need to fast. Reducing your overall calorie intake through standard dieting is just as effective as intermittent fasting for these specific heart health markers. Focus on the total amount of food you eat rather than when you eat it for these outcomes.

Intermittent fasting and continuous energy restriction produce similar improvements in fasting plasma glucose levels, with no statistically significant difference between the two methods.

If your goal is to improve blood sugar levels, you do not need to fast. Reducing your overall calorie intake through standard dieting is just as effective as intermittent fasting for glycemic control. Focus on the total amount of food you eat rather than when you eat it for these outcomes.

A 7-day diet-induced energy restriction of 50% TDEE reduces body mass and fasting blood glucose without eliciting compensatory decreases in basal metabolic rate (BMR) or physical activity energy expenditure (PAEE) in overweight and obese adults.

If you are overweight or obese, a strict 7-day liquid diet cutting your calories in half can produce initial weight loss and improve blood pressure and glucose without causing your body to immediately slow down its metabolism or reduce your spontaneous movement. This suggests short-term aggressive restriction can be a viable strategy for initial health improvements, though long-term maintenance requires different strategies.

A 12-week very low-calorie ketogenic diet (800-1000 kcal/day, 70% fat, 20% protein, 10% carbs) significantly reduces body weight and body fat percentage in overweight/obese adults, but also significantly decreases resting metabolic rate (RMR) and total energy expenditure.

A 12-week very low-calorie ketogenic diet (800-1000 calories, high fat) leads to significant fat loss in obese individuals, but it also significantly slows down your resting metabolism. This metabolic slowdown is a normal adaptive response to severe calorie restriction and should be expected. Long-term maintenance requires careful refeeding strategies to mitigate metabolic adaptation.

Intermittent Fasting (IF) produces weight loss comparable to continuous caloric restriction, but is generally not recommended for Type 2 Diabetes patients due to hypoglycemia risk.

Intermittent fasting can help you lose weight just as well as counting calories every day. However, if you have Type 2 Diabetes, do not try this without a doctor's supervision due to the risk of low blood sugar.

Aerobic exercise combined with 16:8 TRE yields greater reductions in body weight and fat mass than resistance training combined with 16:8 TRE.

If you prefer resistance training, adding 16:8 TRE may still help with fat loss, but the additional benefit from TRE appears greater when combined with aerobic exercise. For maximal short-term fat loss with TRE, aerobic exercise may be the more synergistic choice.

Intermittent fasting (IF) and time-restricted feeding (TRF) reduce oxidative stress and inflammation in Type 2 Diabetes by activating AMPK and SIRT3, which promotes autophagy and mitochondrial biogenesis.

Consider time-restricted feeding by limiting your eating window to 8-10 hours per day. If using intermittent fasting, restrict energy intake by 60% on 2-3 days a week. Monitor blood glucose closely, especially if taking diabetes medication, to avoid hypoglycemia.

Intervention with intermittent fasting reduces lipotoxicity in MASLD patients more effectively than switching to a normal diet.

If you have MASLD, try intermittent fasting. According to the review, it reduces liver fat toxicity better than just switching to a normal diet. You don't need to know the exact hours, but the pattern of fasting helps your liver recover.

Obese gut microbial communities exhibit higher branched-chain amino acid (BCAA) catabolism and hexanoic acid production, which may negatively impact energy balance and metabolic health.

Obese gut bacteria may metabolize proteins differently, producing metabolites like hexanoic acid that could affect energy balance. This highlights why metabolic health in obesity is complex and not just about calorie intake.

Meal timing is not associated with body composition (fat mass, lean mass, or BMI) in young adults, regardless of sex.

Changing when you eat will not directly change your weight or body fat percentage. Focus on total calorie intake and exercise for body composition changes. However, timing may still be useful for metabolic health markers like insulin sensitivity.