Browse the evidence

BCAAs can stimulate mitochondrial biogenesis via the eNOS/NO/SIRT1/PGC-1α and mTOR/YY1 pathways, but this effect is tissue-specific and can be overridden by high levels of saturated fatty acids which suppress PGC-1α.

BCAAs can support mitochondrial health by stimulating biogenesis pathways, but this benefit can be canceled out by a diet high in saturated fats. To support mitochondrial function, combine BCAA intake (or natural sources) with a balanced diet low in saturated fats.

Diet order effects on energy balance and body composition are not observed when comparing Ultra-Processed Foods (UPF) to Minimally Processed Foods (MPF) if the diets are matched for macronutrients, energy density, and fiber.

When comparing ultra-processed foods to minimally processed foods, the physical properties of the food (energy density, fiber, volume) matter more than the processing status itself for determining intake. In this study, when UPF and MPF were matched for these properties, there was no difference in weight loss or energy intake based on which diet was eaten first. This suggests that formulating UPF to match the fiber and density of whole foods may mitigate overeating behaviors.

Caloric restriction (CR) attenuates the age-associated increase in Ink4a/Arf expression in specific tissues (kidney, ovary, heart, testis), correlating with reduced pathology and extended longevity.

Caloric restriction can reduce the expression of aging-related genes like p16INK4a in certain organs (kidney, heart, etc.), which is linked to reduced disease. This suggests that managing calorie intake may help slow biological aging in specific tissues, although the effect is not uniform across all organs.

Variability in resting skeletal muscle metabolism is a major determinant of interindividual differences in resting energy expenditure (BMR and SMR), independent of body composition.

Your resting metabolic rate isn't just about how much muscle you have, but how metabolically active that muscle is. People with 'low' metabolic rates may be predisposed to weight gain. While you cannot easily change your genetics, understanding that muscle metabolism varies among individuals highlights why standard calorie predictions often fail for some people.

Global average consumption of sugar-sweetened beverages (SSBs) in adults is approximately 0.58 servings (8 oz) per day, with significant regional and demographic heterogeneity, where consumption is highest in younger adults and specific regions like the Caribbean.

Track your sugar-sweetened beverage intake, as the global average is nearly half a serving (8 oz) per day. Be aware that younger adults and those in high-consumption regions (like the Caribbean) drink significantly more. Reducing SSBs is a primary lever for improving metabolic health, alongside managing fruit juice which, despite being 'natural,' contributes to sugar load and dental issues.

Dietary fat intake (both long-chain and medium-chain triglycerides) does not increase postprandial fat oxidation rates, leading to positive fat balance and net fat storage when consumed with carbohydrates.

Eating dietary fat does not trigger your body to burn that fat for energy. Instead, when you eat fat alongside carbohydrates, your body stores the fat. To lose body fat, you must create an overall energy deficit, as simply changing the fat content of your meals does not increase fat burning.

Low fasting muscle sympathetic nerve activity (MSNA) predisposes individuals to body weight gain by reducing resting metabolic rate and energy expenditure.

Your body's 'idle speed' (metabolic rate) is partly controlled by your sympathetic nervous system. If your baseline nerve activity to muscles is low, your body burns fewer calories at rest, making weight gain more likely even without overeating. This is a physiological predisposition, not a character flaw.

Females have a significantly lower sedentary 24-hour energy expenditure (24EE) than males, even after adjusting for fat-free mass, fat mass, age, and spontaneous physical activity.

Women naturally burn about 100-125 fewer calories per day than men of similar size and activity levels. This is a small but real physiological difference. To manage weight, women may need to be slightly more precise with caloric intake or slightly more active than men with similar body composition, but the difference is manageable and not a barrier to health.

The thermic effect of food (TEF) increases linearly with caloric intake and is independent of leanness or obesity when meals are normalized to fat-free mass.

If you are obese, your body does not necessarily process food calories differently than a lean person's body. The increase in energy expenditure after eating scales directly with how much you eat, regardless of your weight. Focus on the total amount of calories consumed rather than assuming your body is uniquely efficient at storing them.

Approximately two-thirds of the variability in Body Mass Index (BMI) among individuals within the same population is attributable to genetic factors rather than environmental differences.

Your body weight is heavily influenced by your genetics (about 67% of the variation). This means standard 'eat less, move more' advice may be less effective for you than for others because your biology fights back. Focus on environmental changes (like access to healthy food) and targeted therapies rather than just blaming yourself for lack of willpower.

Intensive lifestyle intervention does not significantly improve objective physical examination measures of diabetic peripheral neuropathy (such as vibration sense or monofilament light touch) compared to control, except for a slight preservation of light touch sensation when both feet are considered together.

While lifestyle changes improve how patients *feel* (less pain, numbness), they may not always reverse objective nerve damage detectable by standard physical exams like monofilament testing. This highlights the importance of symptom management and prevention of progression, even if structural reversal is not achieved.

Adding a Very Low-Calorie Diet (VLCD) to a Weight-Management Programme (WMP) is not cost-effective compared to a WMP alone, despite producing greater short-term weight loss.

For those with severe obesity, adding a Very Low-Calorie Diet to a standard weight management program provides more weight loss in the first year but is not considered cost-effective. Standard WMPs are a more economically sound approach.

Lateral hypothalamic area (LHA) neurons coordinate energy balance by integrating peripheral nutrient cues with ingestive, locomotor, and arousal behaviors.

Understanding how the brain coordinates hunger, activity, and sleep is key to managing weight. The LHA plays a central role in this process, suggesting that treatments for obesity or eating disorders might target specific neuronal populations within this area.

GLP-1 receptor agonists do not significantly increase energy expenditure in humans, despite evidence in animal models.

Don't expect GLP-1 drugs to burn extra calories at rest. They work by reducing food intake.

Sustained caloric restriction in non-obese adults leads to a statistically significant but clinically small loss of bone mineral density (BMD) at the hip and spine, increasing fracture risk by an estimated 0.2% over 10 years.

If you restrict calories, expect some bone density loss. Take calcium and vitamin D as recommended, and monitor your bone health, although the increased fracture risk is very small.

Caloric restriction in non-obese adults increases the incidence of adverse events related to the nervous, musculoskeletal, and reproductive systems, particularly in normal-weight individuals compared to overweight individuals.

If you are already lean, be aware that CR may cause more side effects like fatigue, muscle pain, or menstrual issues than if you were overweight. Monitor these symptoms closely.

Adding Very Low Calorie Diets (VLCD, ≤800 kcal/day) to a standard low-intensity weight management program (WMP1) is not cost-effective compared to WMP1 alone.

For patients with severe obesity, adding very low-calorie diet meal replacements (≤800 kcal/day) to a standard 12-week behavioral weight management program is not a cost-effective strategy. The standard program alone provides better value for money. Patients should focus on sustainable behavioral changes rather than expensive, restrictive meal replacements.

In obese patients with type 2 diabetes (BMI ≥30), intentional weight loss is associated with a statistically significant increase in all-cause mortality.

If you are obese (BMI ≥30) and have type 2 diabetes, intentional weight loss might actually increase your risk of death compared to maintaining your weight. Discuss this specific risk with your doctor, as standard weight loss advice may not apply to your long-term survival.

Supervision has a trivial and statistically non-significant impact on body composition outcomes (body fat %, fat mass, fat-free mass) compared to unsupervised training.

Do not expect a coach to help you lose fat or gain muscle mass more than you would on your own, provided you follow the program. Focus on consistency and progressive overload. Supervision is more valuable for learning complex lifts and maximizing strength than for changing body composition.

In healthy adults, total energy expenditure (TEE) is a repeatable, durable trait that is not associated with short-term changes in body weight or body composition, meaning low TEE is not a risk factor for weight gain and high TEE is not protective against fat gain.

Stop blaming your weight on a 'slow metabolism.' This study shows that in healthy adults, metabolic rate is a stable trait and does not predict who gains weight or fat. Whether you burn calories fast or slow, it doesn't inherently protect you from or cause you to gain fat. Focus on the net energy balance (what you eat vs. what you move) rather than trying to 'boost' your metabolism, as your baseline expenditure is likely fixed and repeatable.

Controlled caloric excess (1.4x maintenance) for 8 weeks in healthy adults causes significant increases in visceral adipose tissue, systemic inflammation, insulin resistance, and functional cardiovascular risk markers (abnormal circadian blood pressure variability and endothelial dysfunction).

If you are healthy and maintain your weight, eating 40% more than you need for just two months will still damage your blood vessel function and increase blood pressure variability. You do not need to be overweight to suffer these early cardiovascular risks from overeating.

Bariatric surgery is the most effective intervention for reducing epicardial fat volume and improving HFpEF outcomes, superior to modest lifestyle changes.

For obese HFpEF patients, bariatric surgery is the most effective way to reduce epicardial fat and improve heart function. It reduces EAT more effectively than modest lifestyle changes. Consult with a bariatric specialist to see if you are a candidate.

Predictive equations for Resting Energy Expenditure (Mifflin, Harris-Benedict, Derumeaux, WHO) significantly overestimate individual REE in adolescents with severe obesity, rendering them clinically unreliable for prescribing specific caloric deficits.

Do not rely on standard online calculators or clinic formulas to determine your daily calorie limit if you are an adolescent with severe obesity. These tools often overestimate your energy needs by a significant margin (sometimes nearly double), leading to failed weight loss or unhealthy restriction. Focus on sustainable lifestyle habits and professional guidance rather than precise calorie counting based on these flawed estimates.

Intermittent diet breaks (one week of energy balance every two weeks) during a 25% energy deficit do not improve body composition or resting metabolic rate compared to continuous energy restriction in resistance-trained females.

If you are a resistance-trained woman, taking one-week diet breaks every two weeks during a 25% calorie deficit will not help you lose fat or preserve muscle any better than dieting continuously for the same total time in deficit. You can use breaks if you psychologically need them, but do not expect them to save your metabolism or muscle mass compared to sticking to the deficit continuously.