Browse the evidence

Insomnia disorder is an independent risk factor for the development of mental health disorders, including depression, anxiety, and suicide, suggesting that treating insomnia may have preventive value for these conditions.

Treat insomnia seriously not just for sleep quality, but as a critical step in preventing depression and anxiety. Addressing sleep problems early may reduce the risk of developing these mental health conditions.

Digital Cognitive-Behavioral Therapy for Insomnia (dCBT-I) is a cost-effective and viable method for delivering CBT-I at scale, potentially reducing healthcare expenditures.

If you cannot access a therapist for CBT-I, look for validated digital CBT-I programs. They are increasingly recognized as cost-effective and can provide the same core therapeutic benefits.

Physical activity is inversely associated with insulin resistance and circulating metabolite levels, but these associations are largely attenuated when adjusting for HOMA-IR, suggesting physical activity improves insulin sensitivity directly rather than by lowering specific metabolite levels.

Exercise improves insulin sensitivity directly. While your blood tests might show changes in amino acids after exercising, these changes are likely just a reflection of your improved metabolic health, not the primary mechanism. Don't worry if your amino acid levels don't drop perfectly; focus on the consistency of your physical activity.

Short-term vitamin D3 supplementation (120,000 IU every two weeks for 6 weeks) improves postprandial insulin sensitivity (measured by OGIS) in centrally obese, non-diabetic men, but does not affect fasting insulin sensitivity, lipid profiles, or blood pressure.

If you are a centrally obese man over 35 with low vitamin D, taking 120,000 IU of Vitamin D3 every two weeks for six weeks may help your body handle sugar after meals better. However, do not expect this to lower your fasting blood sugar, improve your cholesterol, or lower your blood pressure. It is a targeted intervention for postprandial sensitivity, not a general metabolic fix.

Mineral deficiencies (specifically Magnesium, Zinc, Iron, Copper, and Selenium) impair immune competence by disrupting innate and adaptive immune cell function and inflammation regulation, whereas maintaining adequate levels through a balanced diet supports optimal immune defense.

Focus on eating a varied diet rich in vegetables, nuts, seeds, whole grains, and lean proteins to naturally cover your mineral needs. You likely do not need supplements unless you are in an at-risk group (like an athlete with a restricted diet, elderly, or pregnant) or have a diagnosed deficiency. If you do supplement, do so under medical guidance to avoid toxicity, as too much of certain minerals (like Iron or Zinc) can actually harm your immune system or feed pathogens.

Magnesium deficiency promotes a pro-inflammatory state by increasing cytokine production (IL-6, TNF-alpha) and oxidative stress, while adequate Magnesium levels help regulate inflammation and support T-cell function.

If you have chronic low-grade inflammation, check your Magnesium levels. Ensuring adequate intake through foods like spinach, nuts, and seeds may help lower inflammatory markers like CRP. Do not self-prescribe high-dose supplements without testing, as balance is key.

Zinc supplementation (>75 mg/day) significantly reduces the duration of common colds, and adequate Zinc status is critical for T-cell maturation and preventing thymic atrophy, though excessive doses (>40 mg/day long-term) can cause immune dysfunction.

If you catch a cold, starting Zinc lozenges or supplements (totaling >75mg/day) within 24 hours may shorten the illness. Do not take high-dose Zinc (over 40mg/day) as a daily long-term supplement, as it can harm your immune system and cause other health issues. Get your Zinc from food sources like beef, oysters, and nuts instead.

Sustainable nonshivering thermogenesis (NST) in adult humans contributes significantly to energy expenditure, amounting to 15% of average daily energy expenditure and up to 5% of basal metabolic rate, primarily mediated by brown adipose tissue (BAT) and potentially skeletal muscle.

Your body naturally burns extra calories when exposed to cold through a process called nonshivering thermogenesis, largely driven by brown fat. This can account for a significant portion of your daily energy use (up to 15% of total expenditure). While obese individuals may have a blunted response, maintaining some level of cold exposure or avoiding excessive insulation can help leverage this metabolic pathway for energy balance regulation.

Increased intake of omega-3 fatty acids (from fish or supplements) improves cardiometabolic health markers (blood pressure, triglycerides, inflammation, insulin sensitivity) in obese and metabolic syndrome patients, independent of weight loss.

Eat fatty fish or take omega-3 supplements to improve your heart health, lower triglycerides, and reduce inflammation. Do not expect this to cause weight loss on its own, but it will support your metabolic health.

Intravenous pretreatment with N-acetylcysteine (150 mg/kg) inhibits the development of fatigue in human skeletal muscle during low-frequency (10 Hz) electrical stimulation, increasing force output by approximately 15% compared to control.

This study demonstrates that a single high-dose intravenous injection of N-acetylcysteine (150 mg/kg) can reduce muscle fatigue during low-intensity, repetitive exercise in healthy men. However, this benefit comes with a high risk of unpleasant side effects (nausea, flushing, dizziness) requiring additional medication (diphenhydramine). Because the intervention requires IV administration and causes significant distress, it is not a practical or recommended strategy for improving exercise performance in healthy individuals. It serves primarily as evidence that oxidative stress contributes to fatigue.

Cotadutide, a dual GLP-1 and glucagon receptor agonist, significantly improves hepatic parameters (AST, ALT, FIB-4, NFS, PRO-C3) and lipid profiles (triglycerides) in patients with type 2 diabetes and obesity, with effects on liver enzymes appearing independent of weight loss.

For individuals with type 2 diabetes and obesity, cotadutide (a dual GLP-1/glucagon agonist) offers significant improvements in liver health markers (like AST, ALT, and fibrosis scores) and triglyceride levels, potentially beyond what standard GLP-1 drugs like liraglutide achieve. This benefit appears linked to the glucagon component of the drug. Treatment involves daily subcutaneous injections, starting at a low dose and titrating up, which helps manage initial gastrointestinal side effects like nausea. Patients should discuss this option with their healthcare provider, especially if they have concerns about liver health or lipid profiles.

Implementing specific health taxes on sugar-sweetened beverages at rates of 20% or higher significantly reduces consumption and improves population health outcomes, whereas lower rates (<20%) generally fail to produce meaningful behavioral change.

To effectively reduce sugar-sweetened beverage consumption, policymakers must implement specific taxes that raise the shelf price by at least 20%. Lower taxes (under 20%) are ineffective because consumers do not react to small price increases, especially if the tax is not clearly visible on the shelf. To mitigate political backlash regarding the regressive nature of these taxes, revenues should be earmarked for health-related spending or subsidies for healthy foods.

Exercise training increases physical activity level (PAL) in young adults only when energy intake is increased to maintain energy balance; otherwise, compensatory reductions in non-exercise activity negate the total energy expenditure increase.

If you start exercising to lose weight or boost activity, you must consciously increase your food intake to match the effort. If you do not eat more, your body will likely reduce your movement during the rest of the day (non-exercise activity thermogenesis), resulting in no net change in your total daily energy expenditure. This is especially true for older adults.

Shifting dietary fat quality from saturated to polyunsaturated (increasing the P/S ratio) consistently lowers plasma cholesterol levels, whereas increasing dietary cholesterol quantity has a marginal effect on plasma cholesterol in the majority of individuals.

Focus on the type of fat you eat rather than strictly avoiding dietary cholesterol. Replacing saturated fats (like those in dairy or fatty meats) with polyunsaturated fats (like vegetable oils) is a more reliable way to lower plasma cholesterol than simply cutting back on eggs or shrimp. Most people's bodies naturally adjust to higher cholesterol intake, but they respond consistently to changes in fat quality.

Chronic antioxidant supplementation (specifically Vitamin C and E) interferes with skeletal muscle adaptation to exercise training by attenuating improvements in insulin sensitivity, mitochondrial biogenesis, and antioxidant capacity.

If you are training regularly, avoid taking high-dose Vitamin C and E supplements. They block the molecular signals your body needs to build mitochondria and improve insulin sensitivity. Let the exercise stress do its job.

Antioxidant supplementation consistently blunts skeletal muscle hypertrophy and strength gains following resistance or high-intensity training, unlike endurance training where performance may be unaffected.

If you lift weights or do high-intensity intervals, do not take Vitamin C or E supplements. They block the signals your muscles need to grow stronger and larger. Focus on the training itself.

Sleep restriction (4-5 hours/night) increases 24-hour energy expenditure by ~5-7% in humans, but this metabolic cost is offset by a disproportionate increase in caloric intake (particularly from post-dinner snacks), resulting in a positive energy balance and weight gain.

If you are sleeping less than 7 hours, do not assume you are burning more calories and can eat more. Your body burns slightly more energy when awake, but your hormones (ghrelin/leptin) drive you to eat significantly more, especially late at night. This extra food intake outweighs the extra energy burned, leading to weight gain. Prioritize 7-9 hours of sleep to protect your metabolic health.

Circadian misalignment (e.g., shift work, eating at night) decreases 24-hour energy expenditure and impairs glucose metabolism, independent of caloric intake and physical activity levels.

If you work night shifts or eat late at night, your body's metabolism is less efficient. Your energy expenditure drops, and your body handles sugar worse. To mitigate this, try to eat your main meals during your biological day (even if it's during your 'day' while working nights) and prioritize getting high-quality sleep during the day. Avoid eating large meals during your biological night.

Sleep restriction (4-5 hours/night) impairs glucose metabolism and insulin sensitivity to levels similar to those seen in pre-diabetic or diabetic populations.

Chronic sleep restriction (4-5 hours/night) can impair your body's ability to regulate blood sugar to levels seen in pre-diabetic individuals. This happens even if you maintain a healthy weight. Prioritize 7-9 hours of sleep to protect your long-term metabolic health and reduce your risk of type 2 diabetes.

Ultra-marathon running causes a significant energy deficit leading to reductions in both body fat and skeletal muscle mass.

If you are preparing for an ultra-marathon, expect to lose some muscle and fat due to the massive energy expenditure. To minimize muscle loss, prioritize high carbohydrate intake during the race and ensure adequate protein intake in the days following the event to support recovery.

Previous race experience, specifically the number of ultra-marathon finishes and personal best marathon time, is the most important predictor of successful ultra-marathon performance.

If you are new to ultra-running, prioritize completing shorter ultra-distances to gain experience. Your personal best marathon time and the number of ultras you have finished are better predictors of your future success than your current fitness level alone. Start with shorter ultras to build this specific experience.

Abdominal and thoracic fat distribution (android pattern) negatively influences lung volume and capacity more significantly than overall BMI alone.

Focus on losing abdominal fat, as it directly restricts your diaphragm and reduces lung capacity. Using tools that measure body composition or waist circumference can be more informative than BMI alone for understanding your respiratory health. Targeting visceral fat through diet and exercise will likely yield the best improvements in your breathing mechanics.

Dietary soy protein reduces body weight and fat mass in obese humans and animals, with effects mediated by increased satiety, thermogenesis, and modulation of lipid metabolism genes.

To use soy protein for weight loss, replace a portion of your animal protein intake with soy protein isolate or soy-based meal replacements. Aim for a diet where 25-35% of your calories come from protein, ensuring you are in a caloric deficit. This approach has been shown to reduce body weight and fat mass more effectively than control diets in short-to-medium term trials, while also improving lipid profiles.

Daily consumption of at least 3 grams of oat beta-glucan reduces total and LDL cholesterol levels by 5-10% in normocholesterolemic or hypercholesterolemic subjects.

To lower your cholesterol, aim for at least 3 grams of oat beta-glucin daily. This is roughly equivalent to one and a half cups of cooked oatmeal or a high-fiber oat cereal. For best results, consume it in a liquid form like oat milk or mixed into a smoothie, as liquids maintain the viscosity needed to bind cholesterol. Ensure your overall diet is low in saturated fats to maximize the benefit.