Browse the evidence

Carbohydrate restriction (approx. 130g/day) improves short-term glycemic control (HbA1c) in Japanese patients with type 2 diabetes compared to energy restriction.

For Japanese patients with type 2 diabetes, limiting carbohydrates to around 130 grams per day may improve blood sugar levels (HbA1c) more effectively than simply restricting total calories. This approach is supported by short-term studies, though long-term data is lacking.

GLP-1RAs and GIP/GLP-1RAs (liraglutide, semaglutide, tirzepatide) cause significant loss of fat-free (muscle) mass in older adults with sarcopenic obesity, posing a risk that may outweigh benefits if not managed.

If you are an older adult with sarcopenic obesity considering GLP-1 medications, expect to lose some muscle along with fat. To protect your strength, you must combine the medication with regular resistance exercise and eat enough protein (1.0-1.2g per kg of body weight). Work with your doctor to start slowly and monitor your function.

Soybean protein supplementation provides superior or equivalent improvements in muscle mass, strength, and recovery compared to animal-based proteins (specifically whey), particularly in non-resistance or mixed training contexts, whereas pea and rice proteins show no unique anabolic advantage over whey.

If you are an athlete looking to build muscle or recover, soy protein is a highly effective alternative to whey, often matching or exceeding its benefits for strength and lean mass. Pea and rice proteins are also effective, performing similarly to whey, so you do not need to pay a premium for whey if you prefer plant-based options. Focus on total protein intake and training consistency rather than obsessing over the source, unless you have specific digestive sensitivities.

Very low carbohydrate (VLC) diets offer short-term advantages in reducing medication use and lowering HbA1c in people with type 2 diabetes, but long-term evidence is limited to 12 months.

If you have type 2 diabetes, a very low carbohydrate diet can help lower your blood sugar and reduce medication needs in the short term (up to 12 months). However, long-term data is scarce, so consider this a short-term tool rather than a lifelong guarantee.

Post-acute COVID-19 patients exhibit high rates of malnutrition risk (48%) and suboptimal protein intake, with gastrointestinal symptoms significantly correlating with reduced caloric consumption.

If you are recovering from COVID-19 and experiencing lingering symptoms like loss of taste, smell, or stomach issues, you are at high risk for malnutrition. Prioritize nutrient-dense foods and consider small, frequent meals if large portions are difficult. Monitor your protein intake, as many patients fail to meet recovery needs.

Protein distribution is skewed in post-acute COVID-19 patients, with less than 4% meeting the per-meal threshold of 0.4 g/kg, limiting muscle protein synthesis stimulation.

Do not concentrate all your protein at dinner. Post-acute COVID-19 patients often fail to meet the 0.4 g/kg per-meal threshold at breakfast and lunch. Add protein sources to morning and midday meals to support muscle recovery.

Consuming a high-fat dinner (60% fat) results in significant positive fat balance and metabolic inflexibility, whereas a low-fat dinner (20% fat) results in fat balance near zero, indicating metabolic flexibility.

If you eat a high-fat dinner, your body may store that fat rather than burning it, leading to a positive fat balance overnight. If you eat a lower-fat dinner, your body is more likely to burn the fat you eat, resulting in zero net fat storage. This suggests that meal composition timing matters for overnight fat balance, especially if you have metabolic inflexibility.

Repeated intensive lifestyle interventions result in a progressively less favorable ratio of fat mass loss to fat-free mass loss, indicating a shift towards preserving less lean mass relative to fat loss with each subsequent intervention.

Be aware that as you lose weight repeatedly, you might lose a higher proportion of muscle relative to fat. To mitigate this, ensure your protein intake is adequate (15-20% of calories as per the study) and incorporate resistance training if possible, although the study used mixed activities.

GLP-1RA therapy frequently leads to inadequate protein intake, resulting in loss of lean body mass and potential sarcopenia.

To prevent muscle loss while on GLP-1 medication, you must consciously prioritize protein in your diet. Aim for 1.2-2.0 grams of protein per kilogram of body weight daily. If you are struggling to eat enough protein, consider high-protein food choices or supplements, and discuss this with your healthcare provider.

The Mediterranean Diet (MedDiet) improves cardiometabolic risk factors, insulin resistance, and hyperandrogenism in PCOS.

Adopt a Mediterranean-style diet: eat plenty of vegetables, fruits, legumes, and whole grains. Use olive oil as your main fat, eat fish and nuts regularly, and limit red meat and processed foods. This pattern helps improve insulin resistance and hormone levels in PCOS.

In individuals with prediabetes, consuming a high-energy breakfast (50% of daily energy) compared to a low-energy breakfast (20%) during prolonged sitting results in significantly higher total daily glucose and insulin exposure, despite similar 24-hour continuous glucose monitoring averages.

If you have prediabetes and sit for long periods, avoid making your first meal the largest of the day. This study found that a high-energy breakfast led to higher overall glucose and insulin exposure compared to a low-energy breakfast, even though the total calories and macros were identical. Consider eating a smaller breakfast and a larger dinner to minimize postprandial glucose spikes during sedentary work.

Moderate consumption of eggs (1-2 per day) is safe and potentially healthy for most individuals, provided they replace refined carbohydrates or unhealthy meats.

You can safely eat 1-2 eggs per day. They are a healthy source of protein and nutrients. Just make sure you are eating them as part of a balanced diet, not alongside refined carbohydrates or processed meats.

Higher intake of whole grains and fruits is associated with lower total cholesterol, LDL-C, and HDL-C levels in long-term plant-based eaters.

Prioritize whole grains and fruits daily. While the cholesterol-lowering effect is modest, it is a consistent benefit. Do not fear small amounts of less-healthy plant foods (like pasta) if they fit your overall healthy pattern, but be aware they may impact other markers like uric acid.

Higher intake of polyunsaturated fatty acids (PUFAs) is uniquely and negatively associated with LDL-C levels in a plant-based diet.

Include sources of PUFAs (nuts, seeds, flax) in your diet. They may help lower LDL-C levels, even if the effect is modest.

Replacing servings of low-quality carbohydrates or animal protein with high-quality carbohydrates or plant protein reduces phenotypic age acceleration (PhenoAgeAccel).

To slow biological aging, focus on swapping food sources rather than just cutting calories. Replace one serving of refined grains, sugary drinks, or animal meat with one serving of whole grains, vegetables, nuts, soy, or plant proteins. This substitution is associated with a significant reduction in biological age markers.

High-quality carbohydrate intake is associated with reduced phenotypic age acceleration, but the relationship is non-linear, with potential adverse effects at excessive intake levels.

While high-quality carbohydrates (whole grains, vegetables) generally slow aging, the benefit is not linear. Very high intake may not provide additional benefits and could be detrimental. Aim for a balanced intake of these foods as part of a substitution strategy rather than maximizing them.

Higher relative intake of dietary protein is inversely associated with the risk of coronary artery disease (CAD), based on observational data.

If you are concerned about coronary artery disease, this study suggests that ensuring adequate protein intake may be beneficial. Higher relative protein intake was linked to a lower risk of CAD. Include protein-rich foods in your diet. Consult your doctor for personalized advice, especially if you have existing kidney conditions.

In older women, substituting total or animal protein with fat or carbohydrates is negatively associated with appendicular skeletal muscle mass (ASMM) in cross-sectional analyses, but this association disappears in longitudinal analyses over 20 years.

For older women, simply eating more protein than fat or carbs might not protect muscle mass in the long run (20 years). While cross-sectional data shows a link between lower protein and lower muscle mass, long-term tracking shows no clear benefit. Focus on overall diet quality and physical activity rather than just maximizing protein intake.

A Moderate Carbohydrate-Low Protein (MCLP) diet is the most effective macronutrient ratio for reducing triglycerides compared to a moderate fat-low protein (MFLP) control diet.

If your main health concern is high triglycerides rather than weight loss, a diet with moderate carbohydrates (30-50% of calories) and low protein (≤30% of calories) is likely more effective than very low-carb diets. This ratio outperforms standard moderate-fat diets for this specific lipid marker.

Specific Carbohydrate Diet (SCD) shows potential for improving disease activity and inflammatory markers in pediatric IBD, with some self-reported benefits in adults, but large-scale adult trials are needed.

The Specific Carbohydrate Diet (SCD) shows promise, particularly in children with IBD, where it has been linked to reduced disease activity and inflammation. In adults, self-reported outcomes are positive, but robust clinical trials are still needed. It may be worth discussing with your gastroenterologist, especially if other treatments are insufficient.

Ketogenic, Mediterranean, and DASH diets are effective for preventing atherosclerosis due to their low carbohydrate content, high vegetable/fruit/berry content, and antioxidant richness.

Adopt a Ketogenic, Mediterranean, or DASH diet to prevent atherosclerosis. Focus on low-carbohydrate, high-vegetable, fruit, and antioxidant-rich foods.

Higher intake of fish and shellfish is associated with a decreased risk of incident symptomatic peripheral arterial disease in individuals with diabetes mellitus.

If you have diabetes, try to include more fish and shellfish in your diet. This study suggests that eating more of these foods over time might help lower your risk of developing peripheral arterial disease, a condition that affects blood flow to your limbs. While the statistical evidence was borderline, it aligns with broader recommendations for heart-healthy eating patterns like the Mediterranean diet.

Higher intake of fat and animal protein is associated with lower mortality, while higher carbohydrate intake increases mortality, according to the PURE trial.

According to the PURE trial, replacing refined carbohydrates with fats and animal protein may be associated with lower mortality, while fruits, vegetables, and legumes remain beneficial.

Low-carbohydrate diets improve long-term cardiovascular risk factors (specifically triglycerides and HDL cholesterol) compared to balanced diets, despite no long-term difference in weight loss.

Even if your weight stabilizes to match a balanced diet after a year, your blood lipid profile may improve on a low-carb diet. Specifically, expect lower triglycerides and higher HDL ('good') cholesterol, which are positive markers for heart health.