Browse the evidence

Body fat percentages of 32-35% in women are associated with adverse skeletal outcomes, suggesting a lower obesity cutoff for older women than the WHO standard of 40%.

For older women, aim for a body fat percentage below 32-35% to protect bone health, rather than relying on the standard 40% cutoff.

Short-chain fatty acids (SCFAs), particularly butyrate, produced by gut bacteria, have protective effects against metabolic diseases by improving gut barrier function and reducing inflammation.

Increase intake of dietary fiber and prebiotics to boost butyrate-producing bacteria. This can improve gut barrier function, reduce inflammation, and support metabolic health.

Prolonged intermittent fasting (e.g., during Ramadan) significantly decreases systemic inflammation, as measured by reduced IL-6 and CRP levels, without requiring weight loss.

Consider incorporating prolonged intermittent fasting (e.g., 16-24 hours) into your routine. This practice has been shown to significantly reduce inflammatory markers like IL-6 and CRP, independent of weight loss.

Insoluble non-starch polysaccharides (specifically cellulose and hemicellulose) act as effective laxatives by providing bulk to gut contents, promoting normal laxation and preventing constipation.

If you struggle with constipation, increase your intake of insoluble fiber found in whole grains, wheat bran, and the skins of fruits and vegetables. This adds bulk to your stool and helps move waste through your digestive system more effectively.

Metformin therapy (2000 mg/day for 48 weeks) improves liver histology and serum ALT levels in approximately 30% of patients with NASH, primarily through weight loss rather than direct insulin sensitization.

For NASH patients, metformin (up to 2g/day) can improve liver health, but only about 3 in 10 people see significant histological benefits. Crucially, this benefit appears driven by the weight loss the drug causes, not its direct effect on insulin. If you do not lose weight on metformin, you are unlikely to see liver histology improvements. Gastrointestinal side effects are common but often manageable with slow dose titration.

Lower adherence to the Mediterranean Diet in women with PCOS is associated with adverse body composition, specifically lower Phase Angle (PhA) and Fat-Free Mass (FFM).

Women with PCOS often have worse body composition (lower muscle mass and cellular health, indicated by Phase Angle) than healthy women of the same weight. Improving diet quality through a Mediterranean approach may help preserve Fat-Free Mass and improve cellular health markers, even if weight loss is not the primary goal.

A Ketogenic Diet (KD) enhances endurance exercise capacity and prevents muscle injury during exhaustive exercise by altering lipid metabolism and IL-6 synthesis, though it may increase intramuscular oxidative stress.

A high-fat, low-carb diet may help endurance athletes by improving fat oxidation and preventing muscle damage, but monitor for increased oxidative stress.

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.

Implementing a 20% tax on sugar-sweetened drinks in the UK reduces the prevalence of obesity by 1.3% (approx. 180,000 adults) and overweight by 0.9% (approx. 285,000 adults) through a mechanism of reduced energy intake driven by price elasticity.

A 20% tax on sugary drinks in the UK is projected to reduce the number of obese adults by 1.3%. This policy works by making sugary drinks more expensive, leading to a modest but significant reduction in consumption and overall energy intake across all income groups.

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.

Transitioning from high school to college is associated with a significant risk of weight gain (≥5% baseline body weight) in approximately 23% of students, primarily driven by reduced physical activity and increased sleep duration.

If you are starting college, be aware that your first semester is a high-risk time for gaining 5% or more of your body weight. This is often linked to becoming less physically active and sleeping more. To prevent this, maintain your pre-college physical activity habits and be mindful of your sleep schedule, as these are key factors in the observed weight gain.

Consuming ≥33% of total daily energy intake during the midday period (11:00–17:00) is associated with a lower risk of being overweight or obese compared to consuming less than 33%.

Shift your largest meal to midday (between 11:00 and 17:00). Aim to consume at least one-third of your daily calories during this window. This timing is associated with a lower risk of obesity compared to eating the same amount in the evening. You do not need to force a large breakfast; simply ensuring your main caloric intake happens earlier in the day may help regulate your overall energy balance.

Consuming ≥33% of total daily energy intake during the evening (17:00–00:00) is associated with a two-fold higher risk of being overweight or obese compared to consuming less than 33%.

Avoid consuming the majority of your daily calories after 17:00. Eating a large proportion of your energy in the evening is associated with a significantly higher risk of obesity. Try to finish your largest meals earlier in the day to mitigate this risk.

Alpha-lipoic acid improves insulin sensitivity and glucose disposal in skeletal muscle by activating AMPK and reducing triglyceride accumulation.

For individuals with insulin resistance or type 2 diabetes, ALA may help improve how muscles handle glucose and fats. This is achieved through activating AMPK, a key energy sensor in cells.

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.

Sedentary lifestyle is a major contributor to the high prevalence of obesity and diabetes in Egypt, particularly among urban populations.

Urban living, especially for high-SES individuals, is associated with high sedentary behavior. This is due to structural factors like high-rise living without elevators and cultural barriers to women's sports participation. To improve health, incorporate more daily movement into your routine, such as taking stairs when possible or engaging in home-based exercises.

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.

Activation of brown adipose tissue (BAT) via uncoupling protein 1 (UCP1) increases energy expenditure and protects against obesity and type 2 diabetes.

Adult humans retain functional brown fat, which burns calories to generate heat. While cold exposure can activate this fat, the paper suggests that targeting UCP1 directly (e.g., via drugs) is a more viable therapeutic strategy for weight management than relying solely on cold exposure.

Skeletal muscle expression of uncoupling protein 3 (UCP3) improves fatty acid oxidation and protects against insulin resistance and type 2 diabetes.

Higher levels of UCP3 in skeletal muscle are associated with better fat burning and lower risk of type 2 diabetes. This suggests that strategies to increase UCP3 expression (like exercise or specific dietary patterns) may improve metabolic health.

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.

Dietary restriction (DR) and intermittent fasting (IF) extend lifespan and improve health markers in animal models and humans, with some evidence suggesting greater longevity benefits in females, though IF may be more feasible for women.

Dietary restriction and intermittent fasting can improve health and potentially extend lifespan, with some animal studies showing greater benefits for females. For women, intermittent fasting (e.g., eating normally on 5 days and restricting calories on 2 non-consecutive days) is a feasible way to reduce weight and improve insulin sensitivity without the extreme deprivation of continuous DR. Consult a healthcare provider before starting, especially if you have underlying health conditions.