Browse the evidence

A mobile app-based behavioral weight loss intervention delivered exclusively via smartphone without human coaching does not produce significant weight loss compared to a control group in young adults over 24 months.

Relying solely on a weight loss app is unlikely to result in significant weight loss for young adults. While apps can help with self-monitoring, they lack the human interaction and accountability that are critical for sustained behavioral change. To lose weight, you likely need a combination of technology and personal coaching or social support.

The Recommended Dietary Allowance (RDA) for linoleic acid (an n-6 fatty acid) is approximately 0.5% of daily calories, which meets the needs of 97-98% of the population, while the Estimated Average Requirement (EAR) is near 0.1%.

Aim for linoleic acid (an n-6 fatty acid) to make up about 0.5% of your total daily calories. This is a quantitative target that meets the needs of almost everyone.

The carbohydrate-insulin model, which posits that high carbohydrate intake causes hyperinsulinemia leading to fat storage and weight gain, is experimentally falsified because low-carbohydrate diets fail to produce the expected fat loss or sustained increase in energy expenditure.

Do not rely on the carbohydrate-insulin model to explain weight loss. Low-carb diets do not inherently increase energy expenditure or fat loss compared to other diets when calories are matched. Focus on sustainable dietary patterns.

A 12-month comprehensive lifestyle intervention targeting modest weight loss (7-10%) and increased physical activity does not significantly improve asthma control (ACQ scores) or lung function in obese adults with uncontrolled asthma compared to enhanced usual care.

If you are obese and have uncontrolled asthma, a standard 12-month lifestyle program focusing on modest weight loss (around 4-5%) and moderate exercise is unlikely to significantly improve your asthma symptoms or lung function. While this is excellent for your heart and metabolic health, you should not expect immediate relief from asthma. You may need to aim for a larger weight loss (10% or more) or discuss other asthma management options with your doctor, as modest changes may not be enough to impact airway mechanics or inflammation in this specific population.

Intentional long-term weight loss in overweight or obese adults with type 2 diabetes increases the risk of frailty fractures (hip, pelvis, upper arm/shoulder) despite not increasing total or hip fracture rates overall.

If you have type 2 diabetes and are planning to lose weight, be aware that this specific intervention (intensive lifestyle change) has been linked to a higher risk of breaking bones in the hip, pelvis, or shoulder area, even if your overall fracture risk doesn't change. To mitigate this, focus on preserving muscle mass through resistance training and ensure adequate calcium and vitamin D intake, as bone loss is a key mechanism for this increased risk.

Bariatric surgery (specifically Roux-en-Y gastric bypass) is the only current obesity treatment effective for long-term weight loss and resolution of comorbidities, whereas non-surgical lifestyle and pharmacological interventions typically produce modest, poorly sustained weight loss.

If you have severe obesity, lifestyle changes and current medications rarely lead to lasting weight loss. Bariatric surgery is currently the only intervention proven to sustain significant weight loss and resolve related health issues long-term. Discuss surgical options with a specialist if you qualify, as non-surgical methods often fail to maintain results.

The vast majority of established obesity-predisposing genetic loci do not significantly influence weight loss or weight regain outcomes in response to lifestyle interventions.

Do not rely on commercial genetic tests for common obesity genes (like FTO) to predict whether a diet or exercise program will work for you. This research indicates that for most genetic variants associated with obesity, there is no significant difference in how well people respond to lifestyle interventions. Focus on proven lifestyle strategies (caloric deficit, physical activity) rather than genetic testing for prediction.

Global dietary intake data is highly available for fruits, non-starchy vegetables, and sugar-sweetened beverages, but critically sparse for iodine, vitamin A, plant protein, selenium, added sugar, and animal protein.

When evaluating global diet quality, recognize that data on fruits, vegetables, and sugary drinks is robust, but data on essential micronutrients (iodine, selenium, vitamin A) and specific protein sources is often missing. This limits our ability to assess diet-related health risks in many populations accurately.

Eight years of intensive lifestyle weight loss intervention does not significantly alter overall cognitive function in adults with type 2 diabetes compared to diabetes support and education.

If you have type 2 diabetes, an intensive 8-year weight loss program did not significantly improve overall cognitive function compared to standard diabetes education. However, it did not harm cognition either. Focus on weight loss for metabolic health rather than expecting immediate cognitive benefits.

Perioperative fish oil supplementation (EPA+DHA) does not increase the risk of major bleeding in cardiac surgery patients and may reduce blood transfusion requirements.

If you take fish oil for heart health, you likely do not need to stop it before heart surgery. This study of over 1,500 patients showed that continuing fish oil did not increase bleeding risk and actually reduced the amount of blood transfused. Consult your surgeon, but current evidence supports continuing supplementation.

A 10-year intensive lifestyle intervention for weight loss and increased physical activity does not improve overall or domain-specific cognitive function in middle-aged and older adults with type 2 diabetes compared to diabetes support and education.

For adults with type 2 diabetes, a 10-year intensive lifestyle program focused on weight loss and exercise did not improve cognitive function compared to standard diabetes education. While lifestyle changes are crucial for cardiovascular health, they should not be relied upon as a primary strategy to prevent cognitive decline in this specific population based on current evidence.

Mitochondrial dysfunction, characterized by ROS overproduction, Ca2+ overload, and structural changes, is a primary driver of cellular senescence and age-related diseases.

Maintaining mitochondrial health is crucial for longevity. This involves managing oxidative stress through a balanced diet, regular exercise, and potentially avoiding excessive ROS-producing activities. Understanding that mitochondria are central to aging helps prioritize interventions that support their function.

Metabolic surgery reduces the risk of microvascular and macrovascular complications, as well as all-cause mortality, compared to non-surgical treatment in T2D patients.

Beyond weight loss, metabolic surgery significantly lowers the risk of diabetes-related organ damage (eyes, kidneys, nerves) and reduces the risk of early death compared to managing diabetes with medication and lifestyle changes alone.

The popular '3,500 kcal/lb' rule for weight loss is mathematically incorrect because it assumes a constant energy density of lost tissue, whereas actual weight loss involves a nonlinear shift between fat and lean mass that changes the caloric equivalent per pound lost.

Stop using the '3,500 kcal per pound' rule to predict your weight loss. It is mathematically flawed because your body loses a mix of fat and lean tissue, and the energy cost of losing that mix changes as you lose weight. Fatter individuals require a larger energy deficit to lose the same amount of weight compared to leaner individuals. Use a dynamic model or track actual progress rather than relying on a static conversion factor.

Leptin regulates glucose homeostasis through direct actions on POMC neurons, but does not regulate food intake or energy balance through direct actions on these same neurons.

Understanding that leptin's effect on blood sugar is distinct from its effect on hunger helps explain why leptin therapy fails for weight loss in most obese individuals (who are leptin resistant) but might still have metabolic benefits. It shifts focus from 'blocking hunger' to 'metabolic flexibility' and non-POMC pathways.

Obesity can result from an intrinsic metabolic disorder that shifts fuel partitioning toward storage and sequestration in adipose tissue, causing 'internal starvation' and compensatory hyperphagia, independent of excessive energy intake.

This paper argues that for some individuals, obesity is driven by a biological defect in how the body handles fuel (partitioning), not just by eating too much. This biological defect traps energy in fat cells, causing the body to feel starved and triggering hunger. While this explains specific pathological cases in animal models, it suggests that for some humans, treating obesity requires addressing these underlying metabolic shifts rather than just focusing on calorie restriction.

Resting energy expenditure (REE) is primarily determined by the mass and specific metabolic rates of organs and tissues, with fat-free mass (FFM) explaining the majority of variance in REE.

Your resting metabolic rate is largely dictated by your body composition, specifically your fat-free mass (muscle, organs, bone). Maintaining muscle mass is key to preserving metabolic rate.

Acute postexercise elevations in systemic anabolic hormones (testosterone, growth hormone, IGF-1) are neither necessary nor sufficient to stimulate muscle protein synthesis or drive resistance exercise training-induced hypertrophy.

Stop worrying about the exact time of day you train or trying to manipulate your hormones for better gains. Whether you train in the morning or evening, or whether your hormones fluctuate during your menstrual cycle, does not significantly change your ability to build muscle. Focus on consistent, progressive resistance training rather than trying to 'optimize' your hormonal environment.

Exaggerated secretion of GLP-1 following RYGB and sleeve gastrectomy is causally responsible for improved postprandial beta-cell function and glucose tolerance, as demonstrated by the reversal of these benefits when GLP-1 receptors are blocked.

Surgery triggers a natural surge in GLP-1, a hormone that boosts insulin and improves blood sugar control. This hormonal boost is so effective that blocking it reverses the surgery's benefits, confirming GLP-1's central role in diabetes remission.

Niacin is no longer recommended for routine use in type 2 diabetes because large clinical trials failed to show significant cardiovascular benefits despite improving lipid parameters.

Do not use niacin to treat high triglycerides or low HDL in type 2 diabetes. Large studies show it does not reduce heart attacks or death, and it may worsen blood sugar control. Stick to statins and fibrates if needed.

Obesity is a biologic disorder caused by alterations in CNS pathways controlling energy balance, not a lifestyle failure remediable by willpower alone.

Stop blaming yourself for your weight. Your body is fighting you due to biological mechanisms, not just willpower. Seek medical treatment for obesity just as you would for high blood pressure.

GLP-1 therapy is associated with significant gastrointestinal side effects (nausea, vomiting, diarrhea, constipation) which are dose-dependent and can lead to discontinuation, although most side effects decrease with continued use.

You will likely experience some gastrointestinal side effects like nausea, diarrhea, or constipation, especially when you start the medication or increase the dose. These symptoms often improve over time. Talk to your doctor about managing these side effects through diet and slow dose titration.

Obesity is fundamentally driven by a disruption in energy balance, mediated by central nervous system resistance to leptin and insulin, and dysregulation of the reward system.

Obesity involves biological resistance to satiety signals (leptin/insulin) and reward dysregulation, meaning willpower alone is often insufficient. Medical interventions that bypass or enhance these signals are often necessary.

Obesity is not caused by a lack of willpower but is the result of complex interactions between individual biological factors and environmental determinants, requiring multifactorial prevention and treatment strategies.

Stop blaming yourself for your weight. Obesity is a complex disease influenced by biology and your environment, not just willpower. Effective management requires addressing both individual health behaviors and the broader environment, such as access to healthy food and safe spaces for activity.