Browse the evidence

High intake of animal protein, particularly red and processed meat, is associated with increased all-cause, cancer, and cardiovascular mortality in middle-aged adults, whereas plant protein is protective.

If you are under 65, try replacing some animal proteins (especially red and processed meats) with plant proteins like legumes, nuts, and seeds. This substitution is linked to lower risks of heart disease, cancer, and early death.

High-fat diets (>46% calories from fat, <21% from carbs) do not improve exercise performance despite increasing fat oxidation.

Do not follow a high-fat, low-carb diet to improve performance. While it may help your body burn more fat, it does not make you faster and can actually hurt your performance, especially in intense or long events.

Self-reported dietary energy intake in population surveys is systematically biased by macronutrient composition, specifically under-reporting protein and over-reporting fat relative to actual expenditure.

When analyzing dietary data or tracking your own intake, do not assume that your macronutrient ratios are accurate if your total calorie count is off. People who under-report calories tend to under-report protein and over-report fat. This bias distorts the perceived relationship between diet and health outcomes, meaning 'healthy' diets may appear even healthier than they are in self-reported data.

Ultra-processed food (UPF) consumption in the UK has increased significantly over an 11-year period (2008-2018), while consumption of unprocessed/minimally processed foods has decreased, indicating a population-level shift toward processed diets.

Your diet has likely shifted towards more ultra-processed foods over the last decade, even if you don't feel it. To counter this, consciously increase your intake of unprocessed or minimally processed foods like fruits, vegetables, and whole grains, as these are declining in the general population.

Co-ingesting protein with carbohydrate during endurance exercise does not improve performance or glycogen resynthesis when carbohydrate recommendations are met.

Do not rely on adding protein to your in-exercise nutrition for performance or glycogen storage. Stick to recommended carbohydrate intakes. Save protein for post-exercise recovery.

Caloric restriction alone in older adults with sarcopenic obesity leads to significant loss of lean muscle mass and grip strength, worsening sarcopenia.

If you are an older adult with obesity, simply eating less (caloric restriction) without exercise can cause you to lose muscle, not just fat. This makes you weaker and more frail. To avoid this, you must combine dietary changes with resistance exercise and ensure you are eating enough protein.

There is no statistically significant association between the intake of total fat, saturated fatty acids (SFA), or polyunsaturated fatty acids (PUFA) and the incidence of cardiovascular disease.

You do not need to fear total fat or saturated fat intake in isolation. This study found that the amount of total fat or saturated fat consumed did not significantly predict cardiovascular disease risk. Instead, focus on the specific types of fats you consume, particularly increasing monounsaturated and omega-3 fats.

High intake of total dietary fats, saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) is not significantly associated with the incidence risk of cardiovascular disease (CVD).

Current guidelines often recommend limiting total fat and saturated fat intake to prevent heart disease. However, this large, long-term study found no significant link between the amount of total fat, saturated fat, or unsaturated fats consumed and the risk of developing cardiovascular disease. This suggests that strictly limiting fat intake may not be necessary for CVD prevention, and attention might be better placed on the quality of fats and the overall dietary pattern.

Isocaloric substitution of total fat or saturated fatty acids (SFA) with other macronutrients (carbohydrates, proteins, or other fats) does not significantly alter the risk of cardiovascular disease.

Replacing saturated fats with carbohydrates, proteins, or other fats does not appear to significantly change the risk of cardiovascular disease, according to this study. This suggests that rigid substitution rules may not be necessary, and a balanced approach to macronutrient intake might be more sustainable.

Consuming a high-protein breakfast (34g) versus a low-protein breakfast (6g) for 12 weeks increases subjective satiety but does not result in significant changes in body composition (fat mass, lean mass, weight) or cardiometabolic health markers in young women with overweight.

Eating a high-protein breakfast (around 34g) will likely make you feel fuller throughout the morning compared to a low-protein breakfast. However, if your goal is weight loss or improved blood markers, simply switching to a high-protein breakfast without other changes (like reducing overall calories or increasing exercise) is unlikely to produce results in young overweight women. The increased satiety did not lead to a significant reduction in daily energy intake or body fat in this study.

Intake of total fat, saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) is not associated with the risk of cardiovascular disease.

Current evidence from this meta-analysis does not support limiting total fat, saturated fat, or monounsaturated fat intake to prevent CVD, as no association was found. Focus on avoiding trans fats instead.

Replacing saturated fatty acids (SFAs) with carbohydrates does not significantly alter coronary heart disease (CHD) incidence, indicating that the specific macronutrient substitution of SFA for carbohydrate is not a primary driver of CHD risk in isolation.

Do not assume that simply swapping saturated fats for carbohydrates will lower your risk of heart disease. This study suggests that the macronutrient swap itself has no significant effect on CHD incidence. Instead, focus on the quality and source of the foods you eat.

Compared with animal protein, plant protein results in lower muscle mass, with a stronger negative effect observed in younger adults (<60 years) than in older adults (≥60 years).

If your goal is maximizing muscle mass, animal protein may offer a slight advantage over plant protein, particularly in younger adults. However, the difference is small, and plant protein is still effective. Focus on getting enough total protein and combining plant sources if possible.

There is no significant difference between plant and animal protein for muscle strength or physical performance.

You do not need animal protein to build strength or improve physical performance. Plant protein is equally effective for these outcomes. Focus on consistent training and adequate protein intake.

Post-exercise supplementation with 40g of whey protein provides no additional benefit to cardiorespiratory fitness or cardiometabolic health adaptations compared to an isocaloric placebo when combined with low-volume high-intensity interval training (LOW-HIIT) in sedentary, healthy adults.

If you are sedentary and start doing low-volume high-intensity interval training (HIIT), you do not need to rush to consume 40g of protein immediately after your workout to get the best heart and metabolic health benefits. Consuming an equivalent amount of calories from carbohydrates (like maltodextrin or even just eating a normal meal) provides the same improvements in fitness and blood pressure. Focus on consistency with the training rather than expensive post-workout supplements.

Replacing saturated fatty acids with omega-6 polyunsaturated fatty acids has a neutral effect on blood pressure.

Switching from saturated fats to omega-6 oils will not significantly lower your blood pressure. If blood pressure management is your primary goal, other dietary strategies (like reducing sodium or increasing potassium) may be more effective, though this substitution still benefits cholesterol levels.

A low-fat diet intervention (targeting 20% of calories from fat) does not reduce the incidence of coronary heart disease, stroke, or type 2 diabetes compared to a control group with minimal dietary guidance.

Do not rely on a low-fat diet as a primary strategy for preventing heart disease or diabetes. Simply reducing fat to 20% without improving the quality of the remaining calories (e.g., replacing with refined carbs) does not improve outcomes.

Supplementing with whey protein, soy protein, or isolated leucine (standardized to ~3g leucine per serving) provides no additional benefit for increasing skeletal muscle mass or strength compared to a placebo when combined with resistance training in previously untrained college-aged males who already consume adequate protein (>1.3 g/kg/day) and increase caloric intake.

If you are a beginner lifter eating enough protein (over 1.3g/kg/day) and eating enough calories to support training, you do not need to spend extra money on whey, soy, or leucine supplements. They will not help you build more muscle or strength compared to a placebo, as long as your total diet is sufficient. Focus on your training and total food intake first.

Long-term carbohydrate manipulation (weeks to months) does not influence strength gains or hypertrophy in strength-trained individuals, provided total caloric and protein intake are adequate.

You do not need to eat a high-carbohydrate diet to build muscle or get strong. Focus on hitting your protein targets and maintaining a caloric surplus (if bulking) or deficit (if cutting). You can choose your carbohydrate intake based on preference, activity level, or metabolic health without sacrificing strength gains.

Obesity is a chronic, relapsing disease driven by a syndemic interaction of macro-systems (climate, globalization, policy) and micro-systems (behavior, environment), rather than solely individual choice.

Stop blaming yourself or others for obesity. Recognize it as a chronic disease shaped by your environment, food systems, and socioeconomic status. Seek medical help and policy changes rather than relying solely on willpower.

Body Mass Index (BMI) is an insufficient and potentially misleading sole diagnostic measure for obesity due to its inability to capture phenotypic heterogeneity and visceral adiposity.

Do not rely on BMI alone to assess your health. Ask your doctor for additional metrics like waist circumference, blood pressure, and blood sugar levels to get a complete picture of your metabolic health.

High-temperature cooking and prolonged storage can decrease protein quality by reducing the bioavailability of essential amino acids, particularly lysine, through the Maillard reaction and protein aggregation.

Avoid charring or overcooking meats and grains. High-temperature methods like grilling or prolonged roasting can chemically alter amino acids (especially lysine), reducing the protein's quality. Moderate cooking is generally better for preserving bioavailability.

A ketogenic diet (defined as <50g carbohydrate/day or blood ketones ≥0.5 mM) has largely neutral or detrimental effects on athletic performance compared to a higher-carbohydrate diet, despite significantly increasing fat oxidation rates.

If your goal is to improve athletic performance (endurance, strength, or power), a ketogenic diet is not recommended. While it increases fat burning, it does not translate to better performance and may actually hinder it, especially in elite athletes or high-intensity efforts. Stick to a higher-carbohydrate diet for optimal results.

Spirulina supplementation does NOT significantly preserve skeletal muscle mass (SMM) during gradual weight loss compared to placebo; both groups lost similar amounts of muscle mass.

Do not rely on spirulina to preserve your muscle mass during a weight cut. This study showed that wrestlers taking spirulina lost the same amount of muscle as those taking a placebo. To preserve muscle, you must ensure your overall protein intake is high (1.6-3.1 g/kg/day) in addition to following your gradual weight loss diet.