Browse the evidence

Reducing saturated fat intake reduces the risk of combined cardiovascular events, primarily driven by a reduction in coronary heart disease events, with no significant effect on all-cause or cardiovascular mortality.

To lower your risk of heart disease events, try reducing your intake of saturated fats (found in red meat, full-fat dairy, butter, etc.). This change is associated with fewer heart attacks and other cardiovascular events. However, don't expect this change alone to significantly extend your lifespan or prevent all heart-related deaths. Focus on a balanced diet rather than just cutting one nutrient.

Co-ingesting protein (0.3-0.4 g/kg) with sub-optimal carbohydrate amounts (<1 g/kg/h) accelerates glycogen synthesis by augmenting insulin release, but has no additional effect when carbohydrate intake is adequate (>1 g/kg/h).

If you cannot eat enough carbohydrates after exercise (less than 1 g/kg/h), adding 0.3-0.4 g/kg of protein can help speed up glycogen recovery by boosting insulin. However, if you are already consuming sufficient carbohydrates (1 g/kg/h or more), adding protein will not further increase the rate of glycogen storage.

Replacing saturated fatty acids (SFA) with polyunsaturated fatty acids (PUFA) reduces cardiovascular disease (CVD) risk, whereas replacing SFA with refined carbohydrates (starches and sugars) has a neutral or adverse effect on CVD risk.

Don't just cut fat; look at what you replace it with. If you cut saturated fat (like butter or fatty meat) but replace it with refined carbs (white bread, sugar), your heart risk may not improve or could get worse. Instead, replace saturated fats with unsaturated fats (like olive oil, nuts, or fish). This substitution, not just calorie cutting, is what lowers cardiovascular disease risk.

Sugar-sweetened beverages (SSB) promote cardiometabolic disease and obesity through mechanisms beyond simple caloric excess, including specific metabolic effects of fructose and promotion of de novo lipogenesis.

Avoid sugar-sweetened beverages. They are linked to higher risks of type 2 diabetes and heart disease through specific metabolic pathways (like liver fat production) that go beyond just adding calories. Water, unsweetened tea, or coffee are better choices.

A very-low-carbohydrate, high-saturated-fat diet leads to greater weight loss and abdominal fat reduction compared to a high-carbohydrate, low-saturated-fat diet, but results in less favorable changes in LDL cholesterol and C-reactive protein.

A very-low-carbohydrate diet may help you lose slightly more weight and abdominal fat than a high-carbohydrate diet over 8 weeks. However, this comes at the cost of less improvement in LDL cholesterol and inflammation (CRP) compared to a high-carbohydrate diet. If you have high cholesterol or inflammation, a high-carbohydrate diet might be a better choice for your cardiovascular markers, even if weight loss is slightly slower.

Sugary beverages contribute to weight gain and adverse metabolic effects (visceral/liver fat) when added to the diet, but replacing sugar calories with other carbohydrates does not change body weight.

Cutting sugary drinks helps you lose about 2-3 kg, but only because you are removing calories. If you replace those calories with other foods, you won't lose weight. Focus on the total calorie reduction, not just the sugar.

Low carbohydrate and low fat diets produce similar long-term weight loss outcomes, with differences largely explained by adherence and individual metabolic status (e.g., insulin resistance).

Don't obsess over whether to cut carbs or fat. Both work if you stick with them. If you have diabetes or insulin resistance, lower carbs might be easier and better for your health markers. Otherwise, choose the diet that fits your lifestyle and allows you to eat less without constant hunger.

The source of saturated fatty acids (SFA) determines their association with coronary heart disease (CHD) risk: SFAs from yogurt, cheese, and fish are associated with lower CHD incidence, while SFAs from red meat and butter are associated with higher incidence.

Focus on the source of your saturated fats rather than just reducing total SFA. SFAs from yogurt, cheese, and fish are associated with lower CHD risk, while SFAs from red meat and butter are associated with higher risk. Prioritize fermented dairy and fish over red meat and butter for heart health.

Graded whey protein supplementation (increasing from 25g to 150g daily over 6 weeks) combined with extreme-volume resistance training results in significant fat loss and lean body mass gains, but does not produce superior skeletal muscle hypertrophy compared to a control dose of whey or maltodextrin.

If you are doing very high-volume resistance training, you do not need to consume massive amounts of whey protein (up to 150g/day) to maximize muscle growth. A moderate dose (25g/day) combined with your training yields similar muscle gains to a graded high dose. However, the high-dose group did lose more fat. Focus on getting enough protein (around 1.6g/kg/day from food + supplements) rather than maximizing whey powder intake.

Higher habitual dairy intake causally increases lean body mass in adults, as evidenced by Mendelian randomization analysis of 182,041 individuals.

To support lean mass maintenance or growth, include dairy in your daily diet. The study suggests a causal link between higher dairy intake and increased lean mass. Aim for multiple servings per day if tolerated, as the benefit appears dose-dependent.

Ultraprocessed food (UPF) consumption is positively associated with body fat percentage, independent of energy expenditure, age, sex, and economic development rank.

If you are trying to manage body fat, the type of food matters as much as the amount. Ultraprocessed foods are linked to higher body fat even when you account for how much you move. Prioritize whole, minimally processed foods to improve satiety and potentially reduce net energy absorption.

Low-carbohydrate diets (<40% energy) are at least as effective as low-fat diets for short-term weight loss and improve triglyceride and HDL cholesterol profiles, but they increase total and LDL cholesterol levels.

If you choose a low-carb diet for weight loss, expect better triglyceride and HDL improvements than a low-fat diet, but monitor your LDL cholesterol closely as it may rise. The weight loss benefit is real in the short term (under 1 year).

In Korean populations, high carbohydrate intake (50-80% of energy) is associated with an increased risk of metabolic syndrome, elevated triglycerides, and lower HDL cholesterol, but a reduced risk of elevated total and LDL cholesterol.

If you eat a traditional Korean high-carb diet, be aware that high carb intake correlates with higher triglycerides and lower HDL. However, it may keep LDL lower. Focus on improving the quality of your carbohydrates (whole grains) rather than just cutting them.

Moderate carbohydrate intake (50-60% of energy) is associated with the lowest all-cause mortality risk, forming a U-shaped relationship where both very low (<40%) and very high (>70%) intakes increase mortality risk.

Aim for 50-60% of your calories from carbohydrates for optimal longevity. Both very low and very high carbohydrate intakes are associated with higher mortality risks.

Moderate carbohydrate restriction (30% energy) inducing weight loss does not negatively affect global cognition or health-related quality of life in patients with type 2 diabetes compared to a conventional diabetes diet.

If you have Type 2 Diabetes, switching to a moderate low-carb diet (around 30% of calories from carbs) for 6 weeks to lose weight will not harm your thinking abilities or how you feel about your health. It performs similarly to standard diabetic diets regarding mental well-being and cognitive function, though you may see a slight, non-significant boost in mental health scores.

Moderate carbohydrate restriction (30% energy) selectively worsens psychomotor speed (measured by SDMT) compared to a conventional diabetes diet, despite no effect on global cognition.

Be aware that switching to a moderate low-carb diet might make you feel slightly slower at processing information or performing quick mental tasks (like the Symbol Digit Test) in the first few weeks. However, this does not appear to affect your overall memory or general thinking ability, and this specific slowdown may improve with longer-term adherence.

Immediate post-exercise nutrient timing does not provide a hypertrophic advantage over delayed intake when total daily protein and energy intake are matched.

Stop stressing about eating immediately after your workout. As long as you consume your daily protein target (approx. 1.6-2.2g/kg) and total calories, the exact timing of your post-workout meal does not significantly impact muscle growth. You can safely wait 1-2 hours or more without losing gains.

Pre-exercise protein ingestion can sustain elevated amino acid levels into the post-exercise period, rendering immediate post-exercise protein dosing redundant for most trainees.

If you eat a protein-rich meal 1-2 hours before your workout, you do not need to rush to drink a protein shake immediately after. The amino acids from your pre-workout meal will still be circulating and supporting muscle repair for hours after you finish training.

Replacing saturated fatty acids with omega-6 polyunsaturated fatty acids lowers LDL cholesterol and non-HDL cholesterol concentrations in a dose-dependent manner.

Incorporating omega-6 rich oils (like corn, soybean, or sunflower oil) into your diet in place of saturated fats (like butter or lard) will lower your LDL ('bad') cholesterol. The more you replace saturated fat with these oils, the greater the reduction in LDL cholesterol.

GLP-1 receptor agonists cause a reduction in lean body mass (25-45% of total weight loss), which may impact mobility and metabolic rate, particularly in older adults or those with sarcopenic obesity.

When you lose weight on GLP-1 medications, you lose both fat and some muscle. About a quarter to half of your total weight loss might be muscle. This can affect your strength and metabolism, especially if you are older. To protect your muscles, focus on eating enough protein and doing resistance exercises (like weight lifting) while on the medication.

Saturated fatty acids (SFAs) promote inflammation and insulin resistance by activating TLR4 and inflammasomes, whereas polyunsaturated fatty acids (PUFAs) mitigate inflammation by suppressing NF-κB and upregulating anti-inflammatory IL-10.

Focus on the quality of your fats. Replace saturated fats (found in red meat, butter) with polyunsaturated fats (found in fish, nuts, olive oil). This shift can help lower inflammation and improve your body's sensitivity to insulin.

Dietary intake, specifically higher consumption of sugars, lactose, and folate, distinguishes probiotic responders from non-responders, suggesting diet modulates probiotic efficacy.

Your diet might determine if a probiotic works for you. In this study, people who responded well to the probiotic tended to eat more sugars, lactose, and folate than those who didn't respond. This doesn't mean you should eat more sugar, but it suggests that your current diet interacts with the probiotic. If you're taking a probiotic for metabolic health, your dietary habits are a key part of the equation.

The nitrogen balance method used to establish the 0.8 g/kg RDA likely underestimates true protein requirements due to methodological limitations, such as ignoring nonlinearity and metabolic adaptation.

Understand that the old '0.8g/kg' rule was based on a flawed measurement method. It is safer to aim higher, especially if you are active or older.

Higher intake of fish and shellfish, dietary fiber, and saturated fatty acids (SFA) is independently associated with a reduced risk of incident atherosclerotic cardiovascular disease (ACVD).

Ensure you are eating at least 300g of fish and shellfish per week and consuming enough dietary fiber (≥2.4g per megajoule of energy). Do not fear saturated fats from whole food sources like dairy, as this study suggests they may be protective when part of a high-quality diet. Focus on the quality of your fats and fibers rather than eliminating them.