Browse the evidence

Dietary interventions, particularly those involving calorie restriction, high protein, or specific macronutrient compositions, can alter gut microbiota composition, with changes often correlating with weight loss outcomes.

Adopting a calorie-restricted diet combined with increased physical activity can positively shift gut microbiota, particularly increasing beneficial bacteria like Bacteroides fragilis and Lactobacillus. These shifts are more pronounced in individuals who achieve significant weight loss.

Technological changes that reduce physical activity in home and market production (sedentary work) significantly increase body weight, accounting for approximately 60% of recent obesity growth.

Your job's physical demands are a major determinant of your weight. If you have a sedentary job, you are statistically likely to weigh significantly more (approx. 3.3 BMI units higher) than someone with a physically active job, independent of how much you eat. To counteract this, you must intentionally increase physical activity outside of work hours, as the 'free exercise' provided by strenuous labor is no longer available.

The same 12-week home-based physical activity intervention significantly improves psychological well-being, specifically vigor and fatigue levels, in early-stage breast cancer survivors, with positive trends in overall mood and body esteem.

If you are feeling fatigued after breast cancer treatment, starting a gentle, home-based exercise routine can actually help boost your energy and mood. Don't wait until you feel 'ready' or 'strong.' Start with just 10 minutes of walking. The act of moving, even in small doses, can help reduce fatigue and improve your sense of well-being over time. The support from a counselor can also help you stay motivated.

In men with type 2 or type 1 diabetes, lower testosterone levels (both total and calculated free testosterone) are independently associated with higher insulin resistance, and longitudinal changes in testosterone inversely correlate with changes in insulin sensitivity.

If you have diabetes and low testosterone, it is likely linked to your insulin resistance rather than just aging. Improving insulin sensitivity through weight loss and exercise may help normalize testosterone levels, though testosterone replacement therapy is not yet proven to be the primary solution.

High intake of olive oil is significantly associated with reduced risk of all-cause mortality, cardiovascular events, and stroke, whereas general monounsaturated fatty acid (MUFA) intake from mixed sources shows no significant protective effect.

Prioritize olive oil as your primary source of monounsaturated fats for heart health and longevity. Simply increasing total MUFA intake without specifying olive oil may not provide the same protective benefits against mortality and stroke, as mixed sources (including animal fats) showed no significant benefit in this analysis.

Light to moderate alcohol consumption (1-14 g/day) is associated with lower all-cause and cardiovascular mortality compared to abstinence or heavy drinking, but heavy consumption increases cancer mortality.

If you drink alcohol, limit yourself to one drink or less per day. This level of consumption is associated with lower all-cause and cardiovascular mortality compared to abstinence or heavy drinking. However, be aware that heavy drinking increases your risk of cancer. If you do not drink, there is no compelling reason to start for health benefits, especially given the cancer risk associated with heavier use.

mTORC1 signaling is the central regulator of skeletal muscle mass, acting as a dual controller that promotes hypertrophy through protein synthesis and prevents atrophy by inhibiting catabolic pathways.

To maximize muscle growth, you must activate the mTOR pathway. This is achieved through resistance training (mechanical load), adequate protein intake (amino acids), and growth factors like IGF-1. Conversely, conditions that suppress mTOR (like severe caloric restriction, aging-related sarcopenia, or high cortisol) will hinder muscle maintenance. Prioritize resistance exercise and sufficient protein to keep this signaling pathway active.

Histidine-containing dipeptides (Carnosine and Anserine) act as powerful intracellular pH buffers that attenuate pH changes in muscles during anaerobic exercise.

Carnosine and anserine help your muscles handle the acidity of intense exercise. This is why they are often studied for performance benefits.

Acute total sleep deprivation (approx. 32 hours) amplifies reactivity in human mesolimbic reward brain networks (VTA, striatum, amygdala, insula) in response to positive emotional stimuli, resulting in a behavioral bias where sleep-deprived individuals rate more neutral stimuli as pleasant compared to rested controls.

If you are sleep-deprived, your brain's reward system is hijacked. You will likely perceive neutral things as more pleasurable and rewarding than they are, and you may feel a temporary, unstable 'high' or euphoria. This state biases you toward impulsive decisions, risk-taking, and potentially overconsumption of rewards (like food or substances). Prioritize sleep to maintain accurate emotional appraisal and decision-making.

Alginate serves as a biocompatible and biodegradable material for drug delivery, including the encapsulation of probiotics and insulin.

Alginate is widely used to deliver medications and probiotics effectively. It protects these substances from degradation and ensures they reach their target in the body. This makes it a valuable component in many health supplements and pharmaceuticals.

Limiting repetition velocity loss to 20% during resistance training yields greater improvements in explosive power (countermovement jump) and preserves fast-twitch muscle fiber types (MHC-IIX) compared to allowing 40% velocity loss, despite producing significantly lower total training volume and less muscle hypertrophy.

If your goal is explosive power (like jumping or sprinting), stop your sets when your bar speed drops by 20% from your fastest rep. Do not push until you are slow or failing. This approach builds power and preserves fast-twitch muscle fibers better than training close to failure, even though you do fewer total reps. If your goal is pure muscle size, you might need to train closer to failure (40% velocity loss).

Prolonged sleep restriction (4 hours/night for 5 nights) increases cardiovascular disease risk by augmenting proinflammatory responses, specifically through elevated IL-17 and C-reactive protein (CRP) levels, which persist even after recovery sleep.

If you consistently restrict your sleep to around 4 hours per night for several days, your body enters a proinflammatory state characterized by high levels of IL-17 and CRP. This state persists even if you sleep normally for two days afterward. Since these markers are linked to cardiovascular disease risk, prioritizing consistent, sufficient sleep duration is critical for long-term heart health, rather than relying on weekend recovery alone.

Consuming 50g of high alpha-linolenic acid (ALA) flaxseed daily for 4 weeks significantly lowers serum total cholesterol by 9% and LDL cholesterol by 18% in healthy women.

Add 50 grams of ground flaxseed to your daily diet for at least 4 weeks to potentially lower your LDL cholesterol by nearly 20%. You can mix it into yogurt, soups, or bake it into bread. This is safe and tastes fine for most people.

Consuming 50g of flaxseed or 25g of flaxseed mucilage with a carbohydrate meal reduces postprandial blood glucose responses by approximately 27%.

If you eat carbohydrates, add 50g of ground flaxseed or 25g of flaxseed mucilage to your meal. This can reduce your blood sugar spike by about 27%, which is beneficial for metabolic health.

Consuming 50g of flaxseed daily for 4 weeks raises plasma and erythrocyte alpha-linolenic acid (ALA) and long-chain n-3 fatty acids, with bioavailability from ground flaxseed flour being equivalent to flaxseed oil.

To boost your omega-3 levels, eat 50g of ground flaxseed daily. It raises your blood ALA levels just as effectively as taking flaxseed oil capsules, and baking it into foods doesn't create harmful oxidation products.

Baking flaxseed into muffins eliminates detectable levels of cyanogenic glycosides (linustatin, linamarin, neolinustatin), addressing safety concerns about raw consumption.

If you are worried about toxins in flaxseed, bake it. Baking muffins with flaxseed destroys the potentially harmful cyanogenic glycosides, making it a safe way to consume it.

Long-term consumption of diets high in fat and/or fructose attenuates insulin and leptin production, leading to increased energy intake and contributing to weight gain and obesity.

If you eat a lot of fat and sugar, your body may produce less of the hormones (insulin and leptin) that tell your brain you are full and have enough energy. This can make you hungrier and lead to weight gain over time. It is not just about 'spiking' insulin with carbs, but how your long-term diet affects these hormonal signals.

Self-administered Food Frequency Questionnaires (FFQs) used in large cohorts provide valid estimates of macronutrient and food group intake, though they may underestimate micronutrient intake compared to 24-hour recalls.

Diet surveys are generally good at tracking big nutrient groups like fat and protein, but might miss precise amounts of certain vitamins and minerals.

Exposure to light at night (LAN), even at dim levels (e.g., 5 lux), disrupts circadian clock gene expression in the suprachiasmatic nucleus (SCN) and peripheral tissues (e.g., liver), which alters metabolic function and contributes to obesity and metabolic disorders.

Minimize exposure to artificial light during your biological night. Even dim light (like from a phone or nightlight) can disrupt your internal clock and metabolism. Use blackout curtains, dim red lights if necessary, and avoid screens before sleep to support healthy hormone regulation and weight management.

High phytate-to-zinc molar ratios in plant-based diets significantly inhibit zinc absorption, compounding zinc deficiency risks in populations relying on cereals.

If you eat a plant-based diet, high phytate levels in cereals can block zinc absorption. To mitigate this, use preparation methods like soaking, germination, or fermentation to reduce phytate and improve zinc bioavailability.

Calcium deficiency risks are high globally (51% in 2011), with animal products being the major source of dietary calcium in many regions.

Calcium deficiency is a major global health issue, affecting over half the world's population. Ensure adequate intake through dietary sources, particularly if you live in or consume foods from regions with high deficiency risks.

Poor sleep quality is significantly associated with poverty and race/ethnicity, with the disparity being most pronounced among impoverished individuals of all racial groups, particularly impoverished Whites who showed the highest odds for poor sleep in adjusted models.

If you are struggling with poor sleep, recognize that your socioeconomic environment and health status are major contributors. For those in poverty, addressing underlying health issues and stress may be more critical for improving sleep than sleep hygiene tips alone. Public health interventions should target these structural determinants rather than placing the burden solely on individual behavior.

Higher body mass index (BMI) is associated with a dose-response increase in the risk of severe COVID-19 outcomes, including hospitalization, ICU admission, invasive mechanical ventilation, and death, with the lowest risk observed at BMIs near the healthy weight/overweight threshold (23.7–25.9 kg/m²).

Maintaining a BMI in the healthy weight range (18.5–24.9 kg/m²) is associated with the lowest risk of severe COVID-19 outcomes, including hospitalization and death. If you have obesity or are overweight, you are at a higher risk for severe illness, and this risk increases with higher BMI categories. Public health recommendations include prioritizing vaccination, masking, and accessing resources to support a healthy weight through nutrition and physical activity.

In recently postmenopausal women, 4 years of oral conjugated equine estrogens (o-CEE) combined with micronized progesterone improves depression and anxiety symptoms, whereas transdermal estradiol (t-E2) provides no mood benefit compared to placebo.

If you are a recently postmenopausal woman considering hormone therapy for mood symptoms, oral conjugated equine estrogens (CEE) combined with progesterone may help reduce depression and anxiety over 4 years. Transdermal estradiol patches did not show these mood benefits compared to placebo. Hormone therapy did not improve cognition in this study.