Browse the evidence

Protein supplementation during endurance training significantly improves time to exhaustion (TTE) with a moderate effect size, despite having no significant effect on maximal oxygen uptake (VO2max) or body composition in the general population.

If you are doing endurance training, adding protein supplements will likely help you exercise for a longer time before exhaustion. However, do not expect this to significantly change your body weight, body fat, or maximum oxygen capacity (VO2max) unless you are currently untrained. Focus on the performance duration benefit rather than body composition changes.

Untrained individuals may experience greater improvements in maximal oxygen uptake (VO2max) from protein supplementation during endurance training compared to trained individuals.

If you are new to endurance training, adding protein supplements might help slightly improve your maximum oxygen uptake (VO2max). This benefit is likely not present if you are already a trained endurance athlete.

Daily oral supplementation with 714 mg nicotinamide and 19 mg pyridoxine accelerates muscle regeneration by increasing muscle stem cell (MuSC) activation and differentiation following eccentric muscle damage.

If you suffer from muscle damage (e.g., from intense exercise or injury), taking 714 mg of Nicotinamide and 19 mg of Pyridoxine daily for about a week may help your body repair muscle faster by boosting stem cell activity. This is distinct from other B3 forms like Nicotinamide Riboside, which may not be effective at these specific cellular targets. Ensure you are healthy and not taking other B-vitamin supplements before starting.

Metformin is effective for preventing type 2 diabetes in prediabetic women, with efficacy varying by menopausal stage and hormonal status.

If you are a woman with prediabetes, metformin is a proven tool to prevent type 2 diabetes, but its effectiveness depends heavily on your menopausal status. It works best for premenopausal women and those who have gone through natural menopause, rather than those who have had their ovaries removed. While lifestyle changes are the first step, metformin is particularly valuable for high-risk individuals (younger, higher BMI, history of gestational diabetes) where lifestyle changes alone may not be enough. Be prepared for potential gastrointestinal side effects, which often improve over time.

In the Iranian adult population, total fat intake (38.3% of energy in adults, 35.88% in the elderly) significantly exceeds the Acceptable Macronutrient Distribution Range (AMDR) of 20-30%, with 55.77% of women and 43.53% of men consuming fat above this limit.

Check your fat intake. In this population, more than half of women and nearly half of men eat too much fat (over 30% of calories). Focus on reducing added fats and high-fat ingredients to align with health guidelines, as this is a major contributor to chronic disease risk.

Vitamin D and retinol insufficiency rates approach 100% in both genders across adult and elderly age groups in Iran, representing a critical public health gap.

Vitamin D and Retinol (Vitamin A) are critically low in this population, affecting nearly everyone. Dietary changes alone may not be enough; consider supplementation or fortified foods to address this widespread deficiency.

Sodium intake exceeds recommended levels in a significant portion of the population, particularly men (72.7% of adult men and 76.6% of elderly men), contributing to cardiovascular risk.

Men in this population consume excessive sodium, with over 70% exceeding recommendations. Reducing sodium intake is crucial for cardiovascular health. Focus on limiting processed foods and added salt.

Dumbbell and cable lateral raises produce equivalent lateral deltoid hypertrophy when shoulder abduction/adduction range of motion is standardized and matched between conditions.

You can use either dumbbells or cables for lateral raises to build your side delts. The key is to match the range of motion (lifting your arm to about 90 degrees) and train to failure for 5 sets, twice a week. Don't worry about which machine is 'better' mechanically; just pick the one you prefer and stick with it.

Performing resistance training to momentary muscular failure (FAIL) results in slightly greater perceived discomfort and exertion, and worsens general post-exercise feelings compared to terminating sets with 1-2 repetitions in reserve (RIR).

If you are struggling to stick to your resistance training routine because you hate how you feel after workouts, try stopping your sets 1-2 reps before you fail (1-2 RIR) instead of going to absolute failure. This study found that while muscle growth and strength gains are similar, training to failure significantly increases discomfort, exertion, and negative feelings. By using 1-2 RIR, you get the same physical benefits with better post-workout feelings, which may help you stay consistent long-term.

Following behavioral weight loss, the body enters a physiological state characterized by adaptive thermogenesis (declines in energy expenditure beyond those attributable to changes in body composition) and increased energy intake, which drive weight regain.

After losing weight, your body biologically fights to regain it by lowering your energy expenditure and increasing hunger. This is a normal physiological response, not a personal failure. To maintain weight loss, you must account for these biological changes, likely requiring ongoing behavioral support and potentially adjusted energy intake/expenditure strategies, rather than relying on the same intensity of effort used during the weight loss phase.

Phentermine-Topiramate produces moderate weight loss (7.87-8.45%) and improves cardiometabolic risk factors, but carries higher risks of neuropsychiatric and cardiovascular side effects compared to GLP-1RAs.

Phentermine-Topiramate is an oral medication that produces moderate weight loss (approx 8%). It is less effective than GLP-1RAs and carries higher risks of side effects like anxiety, paresthesia, and cardiovascular issues. It is not recommended for patients with existing heart disease.

Front-of-pack labeling (FOPL) and sugar-sweetened beverage (SSB) taxes are cost-effective population-level primary prevention strategies that reduce consumption, though their effectiveness varies by socioeconomic status and literacy.

Support policies like sugar taxes and clear food labeling. These are proven to reduce sugary drink consumption and encourage companies to make healthier products. While they may not solve obesity alone, they are a cost-effective way to improve population health.

GLP-1 receptor agonists reduce systolic blood pressure by 1.7 to 10.6 mmHg compared to placebo, contributing to stroke risk reduction.

GLP-1 drugs can help lower blood pressure, which is a key factor in preventing stroke. This effect is seen across different drugs in this class, with some showing reductions of up to 10 mmHg.

GLP-1 receptor agonists reduce the risk of atrial fibrillation by approximately 42% compared to placebo, which is a significant risk factor for stroke.

Taking GLP-1 drugs may also lower your risk of developing atrial fibrillation, a heart rhythm problem that increases stroke risk. This is another way these drugs protect your brain and heart.

Genetically proxied GLP-1R-based multi-target agonists (GIPR/GLP-1R, GCGR/GLP-1R, and GCGR/GIPR/GLP-1R) causally reduce the risk of Metabolic dysfunction-associated steatotic liver disease (MASLD) and its complications, including liver cancer and cardiovascular disease, partly independent of weight loss.

Genetic evidence strongly supports that GLP-1-based therapies (like semaglutide or tirzepatide) reduce the risk of fatty liver disease and its complications (liver cancer, heart disease). This benefit appears to come from improving metabolic health (insulin sensitivity, lipids) directly, not just from losing weight. If you have MASLD, these medications are a promising therapeutic option to discuss with your doctor, regardless of your current weight loss progress.

Discontinuation of semaglutide leads to significant weight regain ('semaglutide rebound'), with studies showing approximately two-thirds of lost weight is regained within one year.

If you stop taking semaglutide, expect to regain about two-thirds of the weight you lost within a year. This 'rebound' effect is common. Plan for sustainable lifestyle changes or discuss long-term management strategies with your doctor before stopping.

Using different prediction equations (Katch-McArdle vs. BIA-derived) to estimate Resting Metabolic Rate (RMR) during weight loss yields significantly different conclusions regarding the presence of metabolic adaptation (MA), with Katch-McArdle suggesting increased metabolic efficiency (increased aRMR) while BIA suggests decreased efficiency (decreased aRMR).

When tracking weight loss, do not rely on a single prediction equation to judge your metabolic health. This study shows that different formulas can contradict each other regarding metabolic adaptation. To minimize this error, prioritize preserving fat-free mass (muscle) through adequate protein intake (approx. 2.0 g/kg FFM as used in the study) and resistance training, as this stabilizes the metabolic rate more reliably than any single calculation method.

Bariatric surgery provides superior, durable weight loss and metabolic improvement compared to non-surgical interventions, including pharmacotherapy.

If you have severe obesity (BMI ≥40, or ≥35 with health issues) and lifestyle changes haven't worked, bariatric surgery is the most effective long-term solution for weight loss and metabolic health. While it has higher upfront costs and risks, it is more cost-effective over time than lifelong medication. Consult a specialist to see if you qualify.

GLP-1 receptor agonists (semaglutide, tirzepatide) and dual agonists produce significant weight loss (15-22.5%) but are associated with lean muscle mass loss and require long-term adherence.

GLP-1 drugs like semaglutide and tirzepatide are highly effective for weight loss (15-22%), but you must take them long-term to maintain results. They can cause muscle loss, so combine them with resistance training and high protein intake. Be aware of GI side effects and contraindications like thyroid cancer history.

Performing bariatric surgery (Roux-en-Y or sleeve gastrectomy) prior to abdominoplasty significantly reduces postoperative complications and improves long-term stability compared to abdominoplasty alone in patients with metabolic syndrome.

If you have significant excess abdominal skin and metabolic issues (high blood pressure, diabetes, or high cholesterol), do not rush into skin removal surgery. You must first lose weight through diet, medication (like GLP-1s), or bariatric surgery until your weight and metabolic markers are stable for at least 6-12 months. This sequence drastically lowers your risk of infection, blood clots, and poor scarring, and ensures the skin removal looks good long-term.

Metformin, alpha-lipoic acid (ALA), and GLP-1 receptor agonists are effective, complementary pharmacological interventions for managing metabolic syndrome, with metformin serving as the universal first-line treatment due to its safety, low cost, and wide availability.

For patients with Metabolic Syndrome, especially in crisis or resource-limited settings, start with metformin as the primary treatment due to its proven safety, low cost, and wide availability. Add alpha-lipoic acid (ALA) to target oxidative stress and insulin sensitivity, and consider GLP-1 agonists if cardiovascular risk is high and resources allow. Simplify regimens and use telemedicine to support adherence, as stress and disruption are major barriers to care.

The MicroSimulation Core Obesity Model (MS-COM) accurately predicts cardiovascular and mortality outcomes in adults with overweight or obesity, including those with normoglycemia, prediabetes, or type 2 diabetes, supporting its use for evaluating obesity management interventions.

For policymakers and health technology assessment bodies, the MS-COM model provides a reliable tool to evaluate the cost-effectiveness of obesity interventions (like semaglutide 2.4 mg) by accurately predicting long-term cardiovascular and mortality risks in overweight and obese adults, including those with diabetes.

Initiation of GLP-1 receptor agonists in adults with obesity or type 2 diabetes is associated with a substantially reduced risk of all-cause mortality, with the survival benefit being more pronounced in patients under 65 years of age and those with cardiometabolic comorbidities.

If you have obesity or type 2 diabetes, starting a GLP-1 RA (like semaglutide or liraglutide) is strongly associated with living longer, especially if you are under 65 or have other heart/kidney risks. While there is a small, early risk of pancreatitis, the survival benefit is substantial. Discuss this risk-benefit profile with your doctor, particularly if you have a history of pancreatic issues.

GLP-1 and GIP/GLP-1 receptor agonists (semaglutide, tirzepatide) cause a significant reduction in skeletal muscle mass (30-40% of total weight loss), posing a risk for sarcopenia, particularly in elderly patients and those with type 2 diabetes.

If you are taking semaglutide or tirzepatide, expect to lose some muscle along with fat. To protect your strength, you must eat more protein (at least 1.2g/kg/day) and perform resistance training 2-3 times per week. This is especially critical if you are older or already have low muscle mass.