Browse the evidence

A clear verdict on the risk-to-benefit ratio of abdominal crunches remains elusive.

Practitioners should be aware of the ongoing debate regarding the effectiveness and safety of abdominal crunches.

The term 'ultra-processed food' emerged in the 1980s and refers to highly-processed convenience foods that are often energy-dense and poor in nutrients.

Practitioners should recognize the historical context and definition of ultra-processed foods when discussing nutrition.

53.5% of participants are at risk of exercise addiction and 46.5% are addicted to exercise.

Practitioners should be aware that a significant portion of regular exercisers may be at risk or addicted to exercise.

The multiple-stage shuttle run (MST) significantly underpredicted VO2max for the entire group (n = 20; p < 0.01) and for runners independently (p < 0.01).

Practitioners should be cautious in using the MST to predict VO2max in these athletic populations.

Obesity may be protective in certain conditions despite being a major causative factor.

Practitioners should consider the protective aspects of obesity in managing patients with certain conditions.

The paper developed the first consensual definition of functional training using an international e-Delphi method.

Practitioners can refer to this consensual definition for clarity in functional training.

A proposal was made to avoid the distinction between functional training and the general concept of training.

Practitioners should consider this proposal when defining and applying functional training.

Common obesity is primarily driven by increased energy intake due to a changing food environment overwhelming homeostatic feedback, rather than defective homeostatic regulation.

Focus on the food environment and intake rather than just blaming willpower or assuming a broken metabolism. The primary driver of the obesity epidemic is increased food intake due to a changing food environment.

Obesity is a disorder of the energy homeostasis system involving the biological defense of an elevated body-fat mass set point, rather than simply the passive accumulation of excess calories.

Understand that your body has a biological 'set point' for body fat that it actively defends. This is why weight loss programs often fail long-term; your body fights back by increasing hunger and decreasing energy expenditure. Effective treatment requires addressing this biological defense, not just relying on willpower or specific diet compositions.

Brown adipose tissue generates heat through uncoupling protein 1 (UCP1), which dissipates energy as heat rather than producing ATP, thereby increasing energy expenditure.

Understanding how brown fat works helps explain why some people might burn more calories at rest, but it does not currently offer a practical intervention for weight loss.

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.

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.

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.

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.

Obesity is fundamentally a chronic metabolic disease characterized by disturbances in energy homeostasis and excessive fat accumulation, driven by a complex interplay of genetic, epigenetic, biological, psychological, and environmental factors.

Understand that obesity is a complex chronic disease, not a moral failing. Effective management requires addressing biological, genetic, and environmental factors, often necessitating medical interventions alongside lifestyle changes.

Energy expenditure can be increased through specific physiological mechanisms independent of physical activity, including UCP1-dependent thermogenesis in brown/beige fat, futile cycling of substrates (creatine, glucose, lipids), and ion pumping (Na+/K+-ATPase, SERCA).

Your body burns calories through several active processes beyond just moving around. These include generating heat in fat tissue (thermogenesis), running 'futile' metabolic cycles that burn energy as heat, and maintaining electrical gradients in cells. While you can't easily control these directly, understanding them helps explain why some medications work better than others. Future treatments may target these specific pathways to help you burn more calories passively.

Intensive lifestyle modification in type 2 diabetes yields only transient weight loss and fails to reduce cardiovascular mortality or clinically relevant endpoints compared to conventional care.

Intensive lifestyle programs for type 2 diabetes can help with short-term weight loss, but they do not prevent heart attacks or death in the long run. Do not feel pressured to achieve perfect lifestyle changes if they do not improve your cardiovascular outcomes, as the evidence for mortality benefit is lacking. Focus on manageable habits rather than extreme regimens.

Body weight regulation is not governed by a single fixed set-point, but rather by a dynamic equilibrium where energy expenditure passively adjusts to match intake, creating a 'zone of indifference' bounded by upper and lower intervention points.

Do not assume your body has a rigid 'set point' that fights against you. Your weight settles at a level where your energy expenditure matches your intake. If your environment changes (e.g., more food, less activity), your weight will drift until your expenditure rises to match the new intake. Understanding this passive feedback helps explain why small, sustained environmental changes lead to gradual weight gain over years.

Alternate-day fasting does not produce superior weight loss, weight maintenance, or cardioprotection compared to daily calorie restriction in metabolically healthy obese adults.

If you are obese and metabolically healthy, alternate-day fasting is not a magic bullet for better weight loss or heart health compared to simply eating less every day. It is equally effective for weight loss but may be harder to stick to long-term, as evidenced by higher dropout rates. Choose the diet you can sustain consistently.

Bariatric surgery (specifically Roux-en-Y gastric bypass) produces the largest and most durable weight loss among current treatments, serving as a benchmark for efficacy, though individual response varies significantly.

If lifestyle and medications fail, bariatric surgery (like RYGB) is the most effective option for significant, sustained weight loss, averaging over 30% loss. It is considered the benchmark for efficacy, though it requires lifelong medical follow-up.

Intermittent energy restriction (IER) diets (time-restricted eating, alternate-day fasting, and 5:2 diet) do not produce superior improvements in body weight, fat mass, or cardiometabolic risk markers compared to continuous energy restriction (CER) when total energy intake is matched.

If your goal is weight loss or better metabolic health, you do not need to adopt a complex intermittent fasting schedule. A standard daily calorie restriction diet is equally effective. Focus on maintaining a consistent caloric deficit rather than restricting your eating window, unless you personally prefer the structure of fasting.

During the refeeding phase after caloric restriction, initial rapid weight regain is predominantly water retention, while actual fat and protein storage occurs more slowly and may be masked by continued water loss in later recovery stages.

When you start eating more after a diet, you will see the scale jump up quickly. Most of this is water, not fat. Later, you might see the scale stall even while you are eating in a surplus, because your body is rebuilding tissue while losing water. Trust the process, not just the scale.

Global age-standardised mean BMI in children and adolescents increased significantly from 1975 to 2016, with obesity prevalence rising from 0.7% to 5.6% in girls and 0.9% to 7.8% in boys, while underweight prevalence decreased.

Track your child's growth using standard BMI percentiles for their age and sex, not just absolute weight. Recognize that both underweight and obesity carry significant health risks. In many regions, underweight remains a larger burden than obesity, so nutritional support should address both ends of the spectrum.

The trajectory of BMI increase in children and adolescents has decoupled from adults in many high-income countries, where childhood BMI trends have plateaued while adult BMI continues to rise.

In high-income countries, public health efforts for children may be showing results (plateauing BMI), but adult obesity continues to rise. This suggests that childhood interventions are working to some extent, but adult lifestyle factors remain unaddressed. Focus on maintaining childhood gains and addressing adult-specific barriers.