Browse the evidence

Within-day energy deficiency, where energy intake and expenditure are assessed in 1-hour intervals, reveals that athletes with menstrual dysfunction spend significantly more time in an energy-deficient state (>300 kcal deficit) than eumenorrheic athletes, even when total daily energy availability appears similar.

Don't just look at your total daily calories. If you train hard, ensure you are eating enough *around* your training sessions. Spreading your intake to avoid large deficits during and immediately after exercise may help protect your hormonal health, even if your total daily calories look okay on paper.

Combined lifestyle interventions (diet, exercise, education, self-monitoring) for gestational diabetes reduce the risk of large-for-gestational age (LGA) infants and decrease neonatal fat mass.

For women with gestational diabetes, combining healthy eating, physical activity, and blood glucose monitoring helps prevent having an overly large baby and reduces fetal fat mass. This approach is the primary recommended treatment.

In children, consuming non-sugar sweeteners is associated with a smaller increase in body mass index (BMI) z-score compared to consuming sugar, but there is no significant difference in body weight.

For children, switching from sugar-sweetened drinks to those with non-sugar sweeteners may help prevent a faster rise in BMI z-score compared to drinking sugary drinks. However, this does not necessarily translate to a difference in actual body weight. It is a modest benefit in a specific metric.

Short sleep duration negatively impacts the efficacy of weight loss interventions, resulting in less fat mass loss and greater weight regain after bariatric surgery compared to adequate sleep.

If you are trying to lose weight, prioritize getting enough sleep. Short sleepers lose less fat mass during a diet and are more likely to regain weight after bariatric surgery. Ensuring 7-8 hours of sleep can enhance the effectiveness of your weight loss efforts.

Vegetarian and vegan diets are associated with lower maternal BMI and reduced risk of overweight/obesity compared to omnivorous diets, but may carry risks of low bone mineral density and osteoporosis if calcium intake is insufficient.

Vegetarian and vegan diets often lead to a healthier BMI and better lipid profiles compared to omnivorous diets. However, you must ensure you are eating enough calories and key minerals like calcium to protect your bone health. Don't fear weight gain, but do fear nutrient gaps.

Butyrate supplementation or increased endogenous production via resistant starch and fiber intake promotes weight management by increasing energy expenditure through AMPK activation and PGC-1α induction, and by reducing energy intake via GLP-1 and PYY secretion.

To leverage butyrate for weight management, focus on increasing your intake of resistant starch and dietary fibers rather than relying solely on supplements. Incorporate foods like cooked-and-cooled potatoes, legumes, and raw bananas into your diet. These substrates feed gut bacteria to produce butyrate, which may help regulate energy expenditure and satiety hormones like GLP-1 and PYY. A clinical trial used 4g of sodium butyrate daily, but dietary modification is the primary natural strategy discussed.

Increased screen time and sedentary behavior during lockdown are associated with higher rates of weight gain and poor sleep quality.

If you must sit for work or study, try to break up long periods of sitting with short movement breaks. The study found high rates of sedentary behavior and screen time during lockdown, which were linked to weight gain and poor sleep.

Extended home confinement during pandemics causes significant body weight and fat mass gain in adults, primarily driven by energy surplus from increased consumption of energy-dense foods and reduced physical activity.

Home confinement creates a 'perfect storm' for weight gain by increasing access to comfort foods and decreasing activity. To counter this, you must actively recreate structure: schedule your meals and exercise, limit access to energy-dense comfort foods, and find non-food ways to manage stress and boredom. Daily self-weighing is recommended as a tool to monitor and prevent gain.

Brown and beige adipose tissue (BAT) enhances systemic glucose tolerance and insulin sensitivity through increased energy expenditure, glucose uptake, and secretion of beneficial factors (batokines), although their role in human insulin resistance resolution is complex and context-dependent.

Activating brown fat through cold exposure or exercise can improve glucose tolerance and insulin sensitivity by burning energy and taking up glucose. However, the extent of this benefit in humans varies, and it is not a standalone cure for obesity-induced insulin resistance.

Combined diet and exercise interventions during pregnancy may reduce the risk of caesarean section compared to standard care, with moderate-quality evidence.

Adopting a healthy diet and exercise routine during pregnancy might lower your chances of needing a caesarean section. While the evidence is not conclusive, the potential benefit exists alongside other health advantages for you and your baby.

High fructose intake is a significant independent environmental risk factor for NAFLD in lean, non-obese individuals, particularly children and adolescents.

If you are lean and have fatty liver, reducing sugary drinks and high-fructose foods is a critical first step. This is especially important for children and adolescents, where fructose intake was the only independent predictor of NAFLD in one study.

Low energy availability (EA), defined as dietary energy intake minus exercise energy expenditure normalized to fat-free mass, is strongly associated with increased risk of menstrual dysfunction, poor bone health, metabolic issues, haematological detriments, psychological disorders, cardiovascular impairment, and gastrointestinal dysfunction in female athletes.

If you are a female athlete, getting enough energy is critical for your overall health and performance. Low energy availability is linked to serious health issues like menstrual dysfunction, poor bone health, metabolic problems, and psychological disorders. It also hurts your performance by decreasing your endurance, coordination, and concentration. Don't rely on BMI to judge your fueling; use screening tools like the LEAF-Q or consult a sports medicine professional if you suspect you are not eating enough to support your activity level.

Low energy availability is associated with negative performance effects including decreased training response, impaired judgement, decreased coordination, decreased concentration, irritability, depression, and decreased endurance performance in female athletes.

If you are a female athlete, getting enough energy is critical for your overall health and performance. Low energy availability is linked to serious health issues like menstrual dysfunction, poor bone health, metabolic problems, and psychological disorders. It also hurts your performance by decreasing your endurance, coordination, and concentration. Don't rely on BMI to judge your fueling; use screening tools like the LEAF-Q or consult a sports medicine professional if you suspect you are not eating enough to support your activity level.

Weight loss interventions, including caloric restriction and bariatric surgery, reduce levels of DNA damage and improve genomic stability in obese individuals.

If you are obese, losing weight is one of the most effective ways to protect your cells from DNA damage. Whether through dietary changes or surgery, reducing body fat lowers the inflammation and oxidative stress that harm your DNA. This benefit occurs even if you don't reach a 'normal' BMI, as any reduction in obesity-related stress improves genome stability.

Metformin reduces visceral fat mass and improves energy metabolism by upregulating adaptive thermogenesis, specifically through the upregulation of UCP-1 in brown adipose tissue and UCP-3 in skeletal muscle.

If you have Type 2 Diabetes or significant visceral fat, metformin (typically 1500mg/day) may help reduce that stubborn belly fat by boosting your body's heat production (thermogenesis). However, it is not a magic weight-loss pill for everyone, and its effectiveness varies. It works best when combined with lifestyle changes.

Intervention with intermittent fasting reduces lipotoxicity in MASLD patients more effectively than switching to a normal diet.

If you have MASLD, try intermittent fasting. According to the review, it reduces liver fat toxicity better than just switching to a normal diet. You don't need to know the exact hours, but the pattern of fasting helps your liver recover.

Exercise and caloric restriction promote longevity and healthy aging by downregulating mTORC1 activity and upregulating autophagy, thereby maintaining proteome quality.

To support longevity, incorporate regular physical activity and consider moderate caloric restriction (20-40% reduction) while ensuring adequate nutrition. These interventions work by inhibiting mTORC1 and boosting autophagy, which clears damaged cellular components. This is not about starvation or extreme exercise, but consistent, moderate lifestyle habits.

Activation of PPARβ/δ by agonists like GW501516 improves fatty acid oxidation and glucose utilization in skeletal muscle, shifting muscle fiber type from fast-twitch glycolytic to slow-twitch oxidative, thereby enhancing exercise capacity and metabolic flexibility.

PPARβ/δ activation helps muscles burn fat and sugar more efficiently and shifts them to be more endurance-oriented. While drugs like GW501516 show this effect in studies, they are not approved for human use. Exercise naturally activates this pathway.

COVID-19 home confinement led to significant weight gain in 38.8% of the Spanish population, with higher BMI and older age being positive predictors of this weight increase.

If you are older or overweight, be aware that lockdown makes weight gain more likely. Focus on maintaining your current activity level and monitoring portions, as these are the strongest predictors of staying stable.

During COVID-19 peak-lockdown periods, US adults experienced significant longitudinal weight gain (mean +0.62 kg) driven by increased consumption of ultra-processed foods, frequent snacking, higher takeout frequency, and reduced physical activity, with these behavioral disruptions persisting for many individuals even after lockdown restrictions eased.

If you gained weight during lockdown, don't assume it will disappear once restrictions end. The study shows that risky habits like eating more ultra-processed foods, snacking frequently, and ordering takeout often persist. To reverse this, you must actively address the root causes: manage stress, improve craving control, and consciously reduce intake of processed foods and screen time, as these behaviors are linked to continued weight gain even after the pandemic context changes.

Resveratrol (150 mg/day) increases energy expenditure and reduces inflammatory markers in obese men, but higher doses (1500 mg/day) may be ineffective for these outcomes.

If using resveratrol for metabolic health, stick to 150 mg/day. Higher doses (1500 mg) have shown no benefit for energy expenditure in obese men. It may help reduce inflammation and increase energy expenditure, but does not directly cause weight loss.

The COVID-19 pandemic led to increased snacking, alcohol consumption, and weight gain in older adults, predisposing them to overnutrition.

If you are an older adult, be aware that the pandemic's stress and isolation may have led you to snack more, drink more alcohol, or gain weight. This is a common reaction. To manage this, try to identify non-food coping mechanisms for stress and prioritize healthy, balanced meals.

L-carnitine supplementation improves glucose disposal and insulin sensitivity in patients with Type 2 Diabetes, primarily by enhancing mitochondrial fatty acid oxidation and reducing toxic lipid intermediates.

For T2D patients, L-carnitine supplementation may help improve how the body uses glucose and insulin sensitivity, particularly by aiding fat burning in the mitochondria. However, it may not significantly lower fasting blood sugar or HbA1c in all individuals, so it should be viewed as an adjuvant therapy rather than a primary treatment.

Individuals with obesity experienced a 52% prevalence of weight gain during lockdown, driven by reduced physical activity and increased snacking, though longitudinal BMI changes were not statistically significant in pooled analyses.

For individuals with obesity, lockdown led to weight gain in more than half of cases, primarily due to less movement and more snacking. While average BMI didn't shift significantly in longitudinal studies, the individual risk is high. Focus on maintaining daily movement and managing snacking triggers, as the loss of structured activity is a major driver of weight gain.