Browse the evidence

Meat and meat products are the primary source of total protein (39.0%), branched-chain amino acids (BCAAs: leucine 39.9%, isoleucine 41.3%, valine 37.4%), and most essential amino acids (lysine 49.2%, histidine 46.6%, threonine 44.7%, tryptophan 41.4%, methionine 44.2%) in the average Polish diet, while grain products are the dominant source for specific non-essential amino acids like cysteine (41.7%), glutamic acid (33.8%), and proline (34.1%).

To ensure adequate intake of essential amino acids, particularly BCAAs and lysine, include meat, poultry, or fish in your diet. If you reduce meat consumption, prioritize grains (for cysteine, glutamic acid, proline) and dairy or legumes to fill the gaps. A combination of these three food groups (meat, grains, dairy) typically covers over 80% of your amino acid requirements.

Lean individuals can develop NAFLD due to visceral adiposity and insulin resistance, and this condition carries similar risks of fibrosis and NASH as obesity-related NAFLD.

Even if you are lean, you can still have fatty liver disease, especially if you are of Asian descent. This is often due to hidden visceral fat. Because lean NAFLD can still lead to serious liver damage (NASH and fibrosis), you should get screened if you have risk factors like family history or metabolic issues, regardless of your weight.

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.

Post-exercise carbohydrate co-ingestion provides no additional muscle protein synthesis (MPS) benefit over adequate protein intake alone following resistance exercise.

You do not need to consume carbohydrates with your post-workout protein to maximize muscle growth. Adequate protein (20-25g) is sufficient to stimulate muscle protein synthesis. Carbs are still recommended for replenishing glycogen stores, but they do not add to muscle building benefits beyond what protein provides.

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.

Lower skeletal muscle lipoprotein lipase (SMLPL) activity is associated with a higher 24-hour respiratory quotient (RQ), indicating a lower ratio of fat oxidation to carbohydrate oxidation, which predisposes individuals to obesity.

Your body's tendency to store fat versus burn it is partly determined by the activity of an enzyme in your muscles called lipoprotein lipase (LPL). Lower levels of this enzyme mean your body oxidizes less fat and more carbohydrates, which is a known predictor of future weight gain. While you cannot directly 'dose' this enzyme, understanding that muscle metabolism plays a critical role in fat partitioning highlights why some individuals gain weight more easily than others despite similar caloric intakes.

Elevating plasma free fatty acid availability during intense exercise (approx. 80% VO2max) increases fat oxidation and spares carbohydrate, but does not enhance performance in exercise lasting approximately 1 hour.

For intense workouts lasting around an hour (like interval training or hard races), eating a high-fat meal beforehand will not help you perform better, even if it changes what fuel your body burns. Your body will still rely heavily on carbohydrates because the intensity is too high to use fat efficiently. Stick to your standard pre-workout nutrition strategy rather than experimenting with high-fat loads for these specific efforts.

Higher dietary intake of alpha-linolenic acid (ALA) is associated with a lower risk of total and non-cardiovascular mortality in older adults, but is not associated with cardiovascular mortality, coronary heart disease, or stroke.

If you are over 65, increasing your intake of plant-based alpha-linolenic acid (found in flaxseed, chia, and walnuts) is associated with a lower risk of dying from non-heart-related causes. However, relying on these plant sources to prevent heart attacks or strokes is not supported by this data. Focus on a balanced diet for cardiovascular health rather than expecting ALA to replace marine omega-3s for heart protection.

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.

Suppressing lipolysis and plasma free fatty acid availability via nicotinic acid ingestion does not impair running performance or capacity during high-intensity endurance exercise (~90 min) in competitive athletes, confirming carbohydrate dependence.

For races lasting around 90 minutes (like a half-marathon), your body relies almost exclusively on carbohydrates for fuel, even if you are well-trained. Trying to force your body to burn more fat (e.g., by fasting or low-carb training) will not improve your performance and may actually reduce your carbohydrate oxidation rates. Ensure you have high carbohydrate availability before and during the race to maximize performance.

Trans fat content in fast food has significantly decreased due to regulatory mandates and reformulation, though naturally occurring trans fats in meat remain.

Trans fats in fast food have significantly decreased due to regulations. However, naturally occurring trans fats in meat remain. Focus on overall calorie and sodium intake rather than just trans fats.

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.

Current evidence does not clearly support cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids (omega-3 and omega-6) or low consumption of total saturated fats for coronary risk reduction.

Current evidence does not strongly support the specific guideline advice to drastically increase polyunsaturated fat intake or strictly limit total saturated fat for the purpose of preventing coronary disease. While trans fats should still be avoided, the distinction between saturated and unsaturated fats may be less critical for heart health than previously believed, according to this large meta-analysis.

High intake of saturated fat and cholesterol is associated with increased risk of fatal coronary heart disease, but this association is largely explained by low dietary fiber intake rather than the fats themselves.

For heart health, prioritize increasing your intake of dietary fiber from whole plant foods (cereals, vegetables, fruit) over simply cutting fat. While high saturated fat intake was linked to fatal heart disease in this study, the risk was significantly reduced when fiber intake was accounted for, suggesting fiber plays a crucial protective role.

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.