Browse the evidence

Ultraprocessed food consumption is a primary driver of obesity due to high energy density, low satiety, and ease of overconsumption.

Reduce your intake of ultraprocessed foods (high in fats, sugars, and energy density). Focus on whole foods like fruits, vegetables, and grains to manage portion sizes and energy intake more effectively.

After 24 months of adherence, there is no significant difference in weight loss or improvements in metabolic risk factors between low-carbohydrate diets and low-fat diets.

If you can stick to either a low-carb or low-fat diet for 2 years or more, you will likely achieve similar weight loss and metabolic improvements. The initial advantages of one over the other fade over time, so choose the one that fits your lifestyle and preferences best.

In crossover diet studies without washout periods, the order of macronutrient manipulation (specifically Low Carbohydrate vs. Low Fat) significantly affects energy balance and body composition outcomes due to carryover effects from gut adaptations.

If you are designing or interpreting a nutrition study that switches between two diets without a break, the order matters. Starting with a high-volume, high-fiber diet (like a Low Carb diet in this study) before switching to a lower-volume diet can lead to significantly greater weight loss than the reverse order, likely because the gut adapts to the volume/fiber of the first diet, reducing intake in the second. For individuals, this suggests that the sequence of dietary changes might impact long-term adherence and results, though this specific mechanism (gut adaptation to mass) is most relevant in controlled settings.

Circadian misalignment and sleep loss disrupt peripheral clocks in skeletal muscle, leading to impaired mitochondrial function, reduced glucose tolerance, and increased insulin resistance.

Prioritize sleep for metabolic health. Poor sleep disrupts your body's internal clock, leading to worse blood sugar control and reduced mitochondrial efficiency. This happens even if you are eating well and exercising. Aim for 7-9 hours of quality sleep to support your metabolic function.

Weight loss interventions, including bariatric surgery and dietary changes, reduce the risk of ventricular arrhythmias and sudden cardiac death in obese patients by correcting electrophysiological abnormalities.

Losing weight through diet or surgery is a powerful way to protect your heart from dangerous rhythms. It doesn't just change your appearance; it physically corrects the electrical signals in your heart (shortening the QT interval) and reduces the metabolic stress that triggers arrhythmias. Discuss weight management strategies with your cardiologist.

Glucagon receptor activation in triple agonists increases energy expenditure and lipid oxidation, contributing to weight loss without causing hyperglycemia when combined with GLP-1 and GIP.

The addition of glucagon receptor activation in triple agonists helps burn more energy and fat, contributing to weight loss without raising blood sugar, thanks to the balancing effects of GLP-1 and GIP.

In older adults (55-70 years), long-term lifestyle interventions for weight loss in prediabetes result in greater sustained weight loss but inferior preservation of fat-free mass and bone mineral content compared to younger adults (25-45 years).

If you are over 55 and losing weight, expect to lose more muscle and bone than a younger person would for the same amount of weight lost. To counter this, you must prioritize resistance training and adequate protein intake, as standard lifestyle interventions alone may not preserve lean mass effectively in this age group.

Men tend to lose more absolute weight than women when undergoing non-pharmacological lifestyle interventions (diet and exercise), although the difference is small.

If you are a woman doing lifestyle changes (diet/exercise), you might lose slightly less weight than a man on the same plan. This is normal. Focus on consistency, as women often have better long-term weight maintenance success.

High consumption of ultra-processed foods (UPF) in young adult women is associated with a long-term increase in fat mass and a decrease in lean mass by early middle age.

For women, consistently high intake of ultra-processed foods (over 35% of daily grams) in your 20s predicts higher fat mass and lower muscle mass in your late 30s. To mitigate this, prioritize whole foods and minimize UPFs, as they are linked to unfavorable body composition changes over time.

Intensive weight loss via energy restriction and increased aerobic exercise induces adaptive thermogenesis (reduced resting energy expenditure beyond mass loss predictions) in both male and female physique athletes.

If you are cutting weight for a competition, expect your metabolism to slow down more than your weight loss would predict. This is a normal biological response called adaptive thermogenesis. It is driven by the energy deficit and increased exercise volume. The good news is that this adaptation is temporary and reverses during recovery.

Physical activity alone is an effective strategy for reducing obesity and related comorbidities, particularly abdominal fat, even without dietary energy restriction.

To lose fat, you do not necessarily need to diet. Engaging in 45-60 minutes of moderate exercise daily is sufficient to reduce body mass and abdominal fat. Focus on consistency rather than extreme intensity if you are not restricting calories.

Exercise interventions typically result in less weight loss than predicted by simple energy balance models due to metabolic and behavioral compensation.

Do not be discouraged if you do not lose weight as fast as you calculate. Your body will try to compensate by making you hungrier or moving less. Focus on the health benefits and consistency rather than just the scale.

Long-term intentional weight loss via intensive lifestyle intervention causes greater bone mineral density loss at the hip in men with type 2 diabetes compared to control, increasing frailty fracture risk.

If you have type 2 diabetes and are planning to lose weight, be aware that men may experience greater bone loss at the hip over the long term. To mitigate this, ensure your weight loss plan includes bone-preserving strategies such as resistance training, adequate calcium and vitamin D intake, and regular monitoring of bone density, rather than relying solely on caloric restriction and walking.

High-intensity interval training (HIIT) elicits higher plasma lactate concentrations than work-matched moderate-intensity continuous training (MICT) during the exercise bout.

If you do HIIT, you will produce more lactate than if you did moderate continuous training of the same work. This is expected and part of what drives the unique adaptations.

Obesity is an independent risk factor for severe COVID-19 outcomes, including hospitalization, ICU admission, and mortality, with risk increasing as BMI increases.

Obesity significantly increases your risk of severe illness, hospitalization, and death from COVID-19. Maintaining a healthy weight is a critical protective factor against severe viral infections.

Weight gain after a type 2 diabetes diagnosis is associated with an increased risk of cardiovascular disease events and all-cause mortality.

Avoiding weight gain after a type 2 diabetes diagnosis is important for reducing the risk of heart disease and death. Maintaining a stable weight is associated with better cardiovascular outcomes than gaining weight.

Faster rates of body mass gain (via larger energy surpluses of 5-15%) primarily increase the rate of fat accumulation rather than augmenting strength or muscle hypertrophy compared to maintenance or moderate surpluses.

If your goal is to maximize muscle and strength gains, you do not need a large caloric surplus. A moderate surplus (approx. 5% above maintenance, leading to ~0.5% body weight gain per 2 weeks) is likely just as effective as a large surplus (15%) for muscle growth, while resulting in significantly less fat gain. Focus on progressive resistance training and adequate protein (>=1.8g/kg) rather than overeating.

Viscous fiber supplementation (median dose 8 g/day) leads to modest reductions in body weight and waist circumference in individuals on ad libitum diets, primarily through increased satiety and energy excretion.

If you are not strictly counting calories, adding about 8 grams of viscous fiber daily (found in foods like oats, beans, or supplements) can help modestly reduce body weight and waist size by making you feel fuller and slightly increasing calorie excretion.

During single-joint resistance training, non-recruited muscles undergo significant volume loss (atrophy), particularly when energy and protein intake are low, suggesting a localized reallocation of muscle mass from untrained to trained tissues.

If you are doing targeted resistance training (like arm curls or leg extensions) and not eating enough calories or protein, your untrained muscles may actually shrink. To maximize net muscle gain, ensure your energy and protein intake are sufficient to support the metabolic cost of building new tissue in your trained muscles, preventing your body from cannibalizing untrained muscles for energy.

Dietary energy density and the proportion of hyper-palatable foods are stronger predictors of ad libitum energy intake than macronutrient composition or gut hormone levels.

To control calories, prioritize foods with lower energy density (more volume for fewer calories) and reduce hyper-palatable combinations (high fat/sugar/sodium). These physical properties drive intake more than the specific macronutrient ratios or hormonal responses.

Greater weight loss during treatment is associated with a lower likelihood of discontinuing GLP-1 RA, and weight regain after discontinuation is associated with a higher likelihood of reinitiating treatment.

Your weight loss progress directly impacts your likelihood of staying on GLP-1 RA. Greater weight loss correlates with better adherence, while weight regain after stopping often prompts patients to restart. If you experience a plateau, discuss it with your provider rather than stopping abruptly, as continued use may still offer health benefits.

Blood pressure reduction from exercise training in MetS patients is conditional on achieving a minimum cumulative exercise duration and lower baseline triglyceride levels.

To lower blood pressure through exercise, you likely need to do more than just 'move'. This study suggests you need to reach a minimum weekly volume (e.g., >100 minutes) and that your baseline triglyceride levels influence how much your blood pressure will drop. If your triglycerides are high, you may need even more volume or different strategies to see BP benefits.

Obesity is primarily caused by a sustained positive energy balance where caloric intake exceeds energy expenditure, driven by biological, behavioral, and environmental factors.

Focus on creating a sustainable energy deficit through modest dietary changes and increased physical activity, while recognizing that biological and environmental factors may make this challenging. Addressing these factors (e.g., sleep, stress, food environment) is crucial for long-term success.

Weight loss achieved via a very-low-carbohydrate, high-saturated-fat diet does not impair endothelial function (measured by flow-mediated dilatation) and improves other cardiovascular risk markers, refuting the hypothesis that such diets inherently damage vascular health.

If you are overweight and have abdominal obesity, losing weight through a very-low-carbohydrate, high-saturated-fat diet does not appear to harm your blood vessel health (endothelial function) over an 8-week period. In fact, other markers of inflammation and clotting risk improved. The key factor seems to be the weight loss itself, which may counteract the negative effects of high saturated fat intake seen in people who don't lose weight.