Browse the evidence

GLP-1 therapy for obesity increases the risk of nutritional deficiencies (e.g., iron, calcium, vitamins A, D, E, K, B1, B12, C) due to significant reductions in caloric intake and potential GI side effects that impair absorption.

Because GLP-1s make you eat much less, you might not get enough essential vitamins and minerals. Watch for signs like fatigue, hair loss, or poor wound healing. Prioritize nutrient-dense foods (vegetables, lean proteins, whole grains) and discuss with your doctor whether you need specific supplements, especially if your calorie intake is very low.

Participation in a structured Patient Empowerment Programme (PEP) for type 2 diabetes reduces all-cause mortality and cardiovascular disease events compared to usual primary care.

If you have Type 2 Diabetes, enrolling in a structured, professional-led education program (like the Patient Empowerment Programme) can significantly lower your risk of dying from any cause or having a heart attack or stroke compared to receiving standard care alone. The program focuses on teaching you skills to manage your disease and make lifestyle changes.

Short-term muscle disuse atrophy (4 days) in humans is driven by declines in muscle protein synthesis (MPS), not by increased muscle protein breakdown (MPB).

If you are immobilized or inactive for a few days, your muscle loss is caused by a drop in your body's ability to build new muscle protein, not by an increase in muscle destruction. To mitigate this, interventions should focus on stimulating muscle protein synthesis (e.g., through protein intake or resistance stimuli if possible) rather than just trying to block breakdown pathways.

The hypertrophic benefit of creatine supplementation is modestly greater in younger adults compared to older adults, although the effect remains small in both groups.

Younger lifters may see a slightly better muscle growth boost from creatine than older lifters, but the difference is small. Older adults should still use creatine as it provides a small benefit, even if the magnitude is lower than in youth.

GLP-1 receptor agonists (semaglutide, liraglutide, tirzepatide) provide a net health benefit for weight loss in non-diabetic adults with obesity, but only when the treatment goal is achieving ≥10% body weight loss; achieving 5% weight loss results in a net harm due to side effects.

If you are considering GLP-1 medications for weight loss without diabetes, understand that these drugs are most effective and 'worth it' if you aim to lose 10% or more of your body weight. Losing only 5% may actually result in a net negative health outcome due to side effects like nausea and vomiting. Ensure you are committed to lifestyle changes (diet and exercise) alongside the medication, and discuss your specific weight loss goals and tolerance for side effects with your doctor.

High-intensity interval training (HIT) in well-trained athletes improves metabolic control (increased fat oxidation, decreased lactate) without attenuating AMPK signaling or ACC phosphorylation in response to exercise.

If you are already a well-trained athlete, doing high-intensity intervals (8x5 minutes at 85% max effort) for just three weeks will significantly improve your body's ability to burn fat during exercise. Crucially, this training does not 'numb' your cellular signaling (AMPK); your muscles remain responsive to the stress, ensuring that your metabolic adaptations continue to occur.

A reduction in waist circumference (WC) is significantly associated with a lower risk of heart failure with preserved ejection fraction (HFpEF), but not heart failure with reduced ejection fraction (HFrEF).

For people with type 2 diabetes, reducing waist size is particularly effective at preventing heart failure with preserved ejection fraction (HFpEF). While overall fat loss helps, targeting central adiposity (waist circumference) offers specific protection against this subtype of heart failure. Monitor your waist as a key health indicator.

Skeletal muscle hypertrophy from resistance training is driven primarily by chronic increases in translational capacity (ribosome biogenesis) and resting protein synthesis, rather than solely by acute post-exercise spikes in protein synthesis.

Focus on consistent resistance training over time to build more ribosomes in your muscles, which increases your baseline protein synthesis. Don't obsess over the exact timing of nutrients immediately post-workout, as total daily protein and long-term training consistency drive hypertrophy more than acute spikes.

Major weight variability (cycling) after type 2 diabetes diagnosis is independently associated with poorer survival and increased cardiovascular risk, whereas steady weight loss or stability is associated with better glycaemic control.

If you have type 2 diabetes, maintaining a steady weight (even if you don't lose much) is likely safer for your heart and longevity than experiencing large swings. If you do lose weight, aim for a slow, steady decline rather than yo-yo dieting. Monitor your weight consistency, not just the number on the scale.

Ingesting carbohydrate during 60 minutes of submaximal running or cycling increases plasma glucose oxidation but does not reduce (spare) mixed muscle glycogen utilization compared to water ingestion.

If you are exercising for about an hour at a moderate intensity (where you can speak in short sentences), drinking a carbohydrate solution will increase the amount of sugar your blood burns for energy. However, it will NOT save your muscle glycogen stores compared to drinking water. You should still consume carbohydrates to maintain blood glucose levels, but do not expect it to extend your endurance by saving muscle fuel during this specific duration and intensity.

Lean body mass is preserved on average in both TRF and MBD groups, but individual responses vary significantly, with some participants losing lean mass despite adequate protein intake.

While your group average lean mass stays stable, individual results vary. Ensure you are lifting weights and eating enough protein (1.4-2.0g/kg body weight or 2.3-3.1g/kg lean mass) to maximize the chance of preserving muscle while losing fat.

Polyphenols and unsaturated fats in the Mediterranean diet mitigate metabolic syndrome risk by suppressing proinflammatory cytokines and lipid peroxidation.

Use extra virgin olive oil as your primary fat source. It contains polyphenols that reduce inflammation and improve metabolic health, countering the negative effects of saturated and trans fats found in Western diets.

SGLT-2 inhibitors and DPP-4 inhibitors produce modest or neutral weight loss effects, respectively, making them less effective for weight management compared to GLP-1 agonists.

SGLT-2 inhibitors offer modest weight loss (3-5%), while DPP-4 inhibitors are generally weight-neutral or have mild effects. They are less effective for weight management than GLP-1 agonists. SGLT-2 inhibitors work by excreting glucose in urine, but compensatory mechanisms limit weight loss. DPP-4 inhibitors are better suited for glycemic control without significant weight impact.

In individuals with type 2 diabetes, a history of cardiovascular disease and higher baseline BMI are associated with modestly poorer cognitive function following an intensive lifestyle intervention compared to standard care.

For individuals with type 2 diabetes who are obese or have a history of cardiovascular disease, intensive lifestyle interventions may not improve cognitive function and could be associated with modestly poorer outcomes compared to standard care. These individuals should discuss potential risks and benefits with their healthcare provider.

Bariatric surgery improves periconception maternal health by normalizing hormonal axes and restoring menstrual cycle regularity, which leads to increased fertility, without increasing the risk of miscarriages or congenital malformations.

If you are considering bariatric surgery and plan to conceive, expect that your fertility will likely improve and menstrual cycles will become regular. However, you must commit to lifelong vitamin supplementation and regular monitoring to prevent deficiencies. Postpone pregnancy until weight loss stabilizes and vitamin levels are normalized to ensure optimal health for you and the fetus.

Behavioral weight management interventions (WLs and WLMs) generally do not exacerbate health inequalities, as most trials find no significant gradient in uptake, adherence, or outcomes across socioeconomic and demographic groups.

Most behavioral weight loss programs work similarly across different social groups. If you are from a disadvantaged background, do not assume the program will fail you; most evidence shows no difference in outcome compared to advantaged groups. However, if you do struggle with adherence, it may be because the program requires high personal agency (time/education) which might be a barrier for you.

Weight loss outcomes (kg or % loss) in behavioral interventions do not consistently favor either 'more' or 'less' advantaged groups, with most trials finding no significant difference in weight loss by socioeconomic or demographic status.

Your socioeconomic background does not predict your weight loss success. While you might face more barriers to starting or sticking with a program, if you do complete it, you are likely to lose the same amount of weight as anyone else.

Saturated long-chain fatty acids (LCFAs) promote insulin resistance and ectopic fat deposition via diacylglycerol (DAG) and ceramide accumulation, whereas medium-chain fatty acids (MCFAs) and polyunsaturated fats do not produce these detrimental effects.

Limit saturated long-chain fatty acids (found in animal fats and dairy) and prioritize unsaturated fats (olive oil, nuts, fish) and medium-chain fats. The source of fat significantly impacts metabolic health.

Dietary fiber intake improves metabolic health by increasing short-chain fatty acid (SCFA) production, which activates G-protein-coupled receptors (GPCRs) to enhance insulin sensitivity, energy expenditure, and gut microbiome diversity.

Aim for 25-38g of fiber daily from whole plant sources. This supports gut health and metabolic function via SCFA production.

Restoring physiological signaling (e.g., via leptin administration) in weight-reduced individuals reverses metabolic adaptations (increased hunger, decreased energy expenditure) and promotes weight maintenance, whereas inducing weight loss alone is insufficient due to strong homeostatic defense of body fat.

If you have lost weight, expect your body to fight to regain it through increased hunger and slower metabolism. Simply losing weight is not enough; long-term success likely requires strategies that address these biological drivers, such as medical interventions that restore normal hormonal signaling, rather than relying solely on willpower.

High consumption of sugar-sweetened beverages (SSBs) amplifies the genetic predisposition to higher body mass index (BMI), such that individuals with high genetic risk scores experience significantly greater weight gain from SSB intake than those with low genetic risk.

If you have a family history of obesity, your sensitivity to sugary drinks is likely higher than average. Reducing or eliminating sugar-sweetened beverages can significantly reduce your genetic risk of gaining weight, even if you have a high genetic predisposition.

The '3500-calorie/pound' rule for weight loss drastically overestimates actual body weight changes over prolonged periods because it fails to account for the reduction in metabolic rate that occurs as body weight decreases.

Do not expect linear weight loss. As you lose weight, your body burns fewer calories, so your initial rate of loss will slow down. Use dynamic models or tools like the NIH Body Weight Planner to set realistic expectations.

Ketogenic diets (less than 50g carbohydrate/day) induce nutritional ketosis, shifting the body's primary fuel source from glucose to ketones and fatty acids, which may provide unique therapeutic benefits beyond weight loss.

If you want to enter ketosis, restrict carbohydrates to under 50 grams per day while maintaining moderate protein intake. Expect your body to switch to burning fat and ketones for fuel. Monitor your electrolytes to avoid initial side effects.

In a 6-month worksite weight loss intervention, a decrease in hunger was the only eating behavior construct that significantly predicted weight loss when controlling for attendance and self-monitoring, whereas changes in restraint and disinhibition were not significant predictors in the final multivariate model.

To maximize weight loss success in a structured program, prioritize strategies that reduce hunger (such as high-fiber, high-protein meals and proper meal timing) over strict cognitive restraint. While attending meetings and monitoring weight are important, the ability to manage hunger levels appears to be the critical behavioral factor that determines how much weight you will lose.