Browse the evidence

Vulnerable populations, including those with diabetes, obesity, and low socioeconomic status, experienced more acute declines in nutritional quality and health during lockdowns compared to the general population.

If you have diabetes, obesity, or live in a high-deprivation area, lockdowns can severely impact your diet. You may experience more acute changes in eating behavior, such as increased consumption of unhealthy foods and decreased adherence to healthy diets. It is crucial to have targeted support and strategies to maintain nutrition during such times.

Pandemic lockdowns led to increased alcohol consumption and a shift in dietary patterns towards higher intake of snacks, sweets, and ultra-processed foods, while decreasing consumption of fresh foods like fruits and vegetables.

Lockdowns led to increased alcohol consumption and a shift towards snacks, sweets, and ultra-processed foods, while decreasing fresh food intake. This resulted in decreased adherence to healthy diets.

Gut microbiota composition directly influences host glycemic control and insulin sensitivity through mechanisms including incretin secretion, short-chain fatty acid (SCFA) production, and bile acid metabolism.

Your gut bacteria play a key role in how your body handles sugar. Eating non-digestible carbohydrates (like inulin and oligofructose) can feed beneficial bacteria that produce short-chain fatty acids and stimulate hormones (GLP-1) that improve insulin response. This suggests that dietary fiber is not just for digestion but is a metabolic tool for glycemic control.

Prebiotic supplementation with non-digestible carbohydrates (e.g., oligofructose, inulin) improves glucose tolerance and insulin response by increasing GLP-1 secretion and SCFA production.

Incorporate prebiotic fibers like inulin or oligofructose into your diet. These are found in foods like chicory root, garlic, and onions, or taken as supplements. They feed gut bacteria that produce beneficial compounds (SCFAs) and stimulate hormones (GLP-1) that help lower blood sugar and reduce appetite.

Long-term shift work, particularly involving night shifts, is strongly associated with increased risks of cardiovascular disease, metabolic disorders (type 2 diabetes, metabolic syndrome), and gastrointestinal issues, largely mediated by circadian misalignment, sleep restriction, and adverse lifestyle behaviors.

If you work nights or rotating shifts, prioritize protecting your sleep environment (dark, cool, quiet) and manage light exposure (bright light during shift, dark glasses on commute home). Be mindful of meal timing; eating late at night can worsen metabolic risk. Recognize that fatigue and digestive issues are common physiological responses to circadian disruption, not just personal failings, and consider strategies to align your schedule with your body's clock where possible.

In individuals with chronic kidney disease (CKD), the presence of sarcopenia (defined by low muscle strength, mass, or performance) significantly increases the risk of all-cause mortality and progression to end-stage renal disease (ESRD).

If you have chronic kidney disease, having low muscle strength or mass is a serious warning sign that increases your risk of death and needing dialysis. You should get your muscle strength checked (e.g., handgrip test) and prioritize physical activity, as it is one of the most effective ways to counteract muscle loss and improve your prognosis.

Blocking myostatin/activin signaling (via ActRIIB blockade) promotes muscle hypertrophy and can reverse cancer cachexia by inhibiting SMAD2/3 signaling and stimulating SMAD1/5/8 pathways.

For those struggling with severe muscle loss, such as in cancer cachexia, therapies that block myostatin/activin signaling show promise in preserving and even increasing muscle mass. This approach targets the root cause of excessive muscle breakdown rather than just stimulating synthesis.

Nudging interventions that combine altering both the properties and the placement of fruit and vegetables yield a significant, medium effect size on increasing selection.

For maximum impact, combine strategic placement (e.g., eye-level, front-of-counter) with property alterations (e.g., attractive presentation, priming, or sizing cues). This dual approach significantly boosts fruit and vegetable selection compared to control conditions.

A eucaloric low-carbohydrate/high-fat diet reverses metabolic syndrome in obese individuals independent of weight loss, primarily by improving atherogenic dyslipidemia (triglycerides, HDL, LDL particle size) and reducing circulating saturated fatty acids and de novo lipogenesis markers.

If you have metabolic syndrome, switching to a low-carbohydrate, high-fat diet can improve your blood lipids and metabolic markers within 4 weeks, even if you do not lose weight. Focus on reducing carbohydrates (to ~6% of calories) and increasing fat, while keeping total calories stable. This approach improves triglycerides, HDL, and LDL particle size more effectively than high-carbohydrate diets, regardless of changes in body weight.

Dietary intake of fermentable carbohydrates and fibers drives the gut microbiota to produce short-chain fatty acids (SCFAs) like butyrate and propionate, which exert anti-inflammatory, anti-cancer, and metabolic regulatory effects on the host.

Prioritize whole plant foods rich in diverse fibers (grains, legumes, fruits, vegetables) to feed your gut bacteria. These bacteria convert fiber into short-chain fatty acids (SCFAs) like butyrate, which reduce inflammation, protect against colon cancer, and support metabolic health. Avoid highly processed high-carb foods that lack fiber, as they do not provide these microbial benefits.

Animal-based diets high in saturated fats and proteins promote the growth of bile-tolerant and proteolytic bacteria, leading to the production of potentially harmful metabolites like TMAO, ammonia, and hydrogen sulfide, which are linked to inflammation and cardiovascular disease.

If you consume animal products, be aware that high intake of red meat and saturated fats can promote gut bacteria that produce harmful metabolites like TMAO and hydrogen sulfide, linked to heart disease and inflammation. Balance animal proteins with high-fiber plant foods to encourage beneficial SCFA production and mitigate these risks.

High-intensity interval training (HIIT) is relatively safe for patients with coronary artery disease or heart failure when administered within supervised cardiac rehabilitation settings, with a major adverse cardiovascular event rate of 1 per 17,083 training sessions.

If you have stable heart disease or heart failure, high-intensity interval training is likely safe when done in a supervised cardiac rehab program. The risk of a serious heart event is extremely low (about 1 in 17,000 sessions). Do not attempt this unsupervised; ensure your condition is stable and you are monitored by cardiac staff.

Health-related claims on food labels significantly increase the likelihood of purchasing and consuming the labeled product compared to identical products without such claims.

If you see a health or nutrition claim on a packaged food, expect that it will make you more likely to buy and eat it than if the package were blank. This is a powerful marketing tool that works in both lab settings and real-world sales data. Use this knowledge to be aware of your own biases when shopping.

A high pre-treatment Prevotella-to-Bacteroides (P/B) ratio predicts significantly greater body fat loss when consuming a high-fiber, whole-grain diet (New Nordic Diet) compared to a standard diet, whereas individuals with a low P/B ratio show no such differential benefit.

If you are trying to lose fat using a high-fiber, whole-grain diet, your gut bacteria composition matters. A simple test of your Prevotella-to-Bacteroides ratio can predict success: if your ratio is high, you are likely to lose significant fat on this diet; if it is low, you may not see benefits over a standard diet, suggesting you might need a different nutritional approach.

Better self-reported sleep quality is associated with better mental health outcomes, specifically showing a U-shaped relationship where both short and long sleep durations correlate with higher depression and anxiety.

Prioritize sleep quality over just duration. If you are sleeping 7-9 hours but still experience high anxiety or depression, your sleep efficiency or continuity may be poor. This study suggests that poor sleep quality is strongly linked to mental health issues, regardless of age. Aim for consistent, efficient sleep rather than just time in bed, and be aware that both sleeping significantly less or significantly more than average can negatively impact mental well-being.

Poor sleep quality is modestly but consistently associated with poorer cognitive performance, particularly verbal phonemic fluency, across the entire adult lifespan (18-98 years).

Maintain good sleep hygiene throughout your life, not just as you age. This study shows that poor sleep quality consistently impacts cognitive performance, especially verbal fluency, from young adulthood to old age. Prioritizing sleep is a key strategy for maintaining cognitive health at any age.

Sodium bicarbonate supplementation (0.2-0.4 g/kg body mass) improves performance in high-intensity sprints lasting ~60 seconds by buffering acid buildup, but causes gastrointestinal distress in many users.

Take 0.2-0.4g of sodium bicarbonate per kg of body weight 60-150 minutes before a ~60 second high-intensity effort. To avoid stomach upset, split the dose, take it with a small carb meal, or use a loading protocol over 2-4 days. Test this in training first, as responses vary widely.

Distributing magnesium intake across multiple small doses throughout the day significantly increases fractional absorption and retention compared to consuming the same total amount in a single bolus.

If you take magnesium supplements, do not take the entire daily dose at once. Split the total amount into 2-4 smaller doses taken throughout the day with meals. This strategy maximizes absorption because the body's active transport mechanisms (TRPM6/7) are more efficient at lower concentrations, whereas high single doses saturate these pathways and lead to lower relative absorption.

High doses of magnesium impair fractional absorption efficiency, whereas low doses are absorbed more efficiently, although absolute absorption increases with dose.

Avoid taking massive single doses of magnesium (e.g., >500mg at once) if your goal is efficient absorption. While you will absorb more total milligrams, the percentage absorbed drops drastically. To maximize efficiency, keep individual doses moderate (e.g., <100-200mg) and spread them out.

Consumption of polyphenol-rich foods (e.g., fruits, vegetables, tea, cocoa) alters gut microbiota composition by promoting beneficial bacteria (Lactobacillus, Bifidobacterium) and inhibiting harmful pathogens, thereby reducing inflammation and improving metabolic health.

Increase your intake of polyphenol-rich foods such as berries, dark chocolate, green tea, and olive oil. These compounds feed beneficial gut bacteria like Lactobacillus and Bifidobacterium while inhibiting harmful ones. This process reduces inflammation and supports metabolic health, even if the polyphenols themselves are processed by gut bacteria rather than directly absorbed.

The Western diet, high in refined carbohydrates, saturated fats, and low in fiber, disrupts gut microbiota diversity and increases the risk of obesity, cardiovascular disease, and metabolic syndrome.

Avoid the Western diet pattern, which is high in refined carbs, saturated fats, and low in fiber. This diet is linked to obesity, cardiovascular disease, and metabolic syndrome. Instead, focus on whole foods, high fiber, and healthy fats to support gut health and reduce disease risk.

High-Intensity Interval Training (HIIT) is an essential component for enhancing endurance performance in athletes, though the optimal intensity distribution and specific prescription remain unclear.

For endurance athletes, HIIT is non-negotiable for performance gains, but you must balance it with moderate volume. Do not prescribe HIIT in isolation; integrate it into a broader program (pyramidal or polarized) to avoid overtraining. The exact type of HIIT (short vs. long intervals) should be periodized based on the specific sport and competition phase.

Vitamin E improves steatohepatitis in nondiabetic patients but is not recommended for diabetic patients due to cardiovascular risks.

If you have fatty liver but do not have diabetes, Vitamin E supplementation may improve your liver inflammation. However, if you have diabetes, do not take Vitamin E for this purpose, as it may increase your risk of heart problems. Consult your doctor to determine if this is appropriate for your specific health profile.

Occupational physical activity, particularly light-intensity activity (LPA) and sedentary time (ST), does not confer the same cardiometabolic health benefits as leisure-time moderate-to-vigorous physical activity (MVPA), and high occupational ST is associated with adverse health outcomes regardless of leisure-time activity.

If you have a sedentary job, your health risk is driven by prolonged sitting, not just lack of exercise. If you have a physically demanding job, your health risk is driven by the lack of cardiovascular intensity and recovery time, not just 'activity.' To mitigate risk, office workers should prioritize leisure-time MVPA and reduce sitting time. Manual laborers should prioritize cardiovascular exercise and recovery, as their job activity may not provide sufficient health benefits and may even increase risk if not managed.