Browse the evidence

High-fructose intake contributes to NAFLD pathogenesis by promoting de novo lipogenesis, hepatic insulin resistance, and leptin resistance.

Limit high-fructose corn syrup and added sugars. High fructose intake drives liver fat production and insulin resistance independently of weight gain. Focus on reducing processed foods and sugary drinks rather than eliminating all natural fruit sources.

A higher dietary fat-to-carbohydrate ratio in African-American children correlates negatively with insulin sensitivity and insulin clearance, and positively with fasting free fatty acids and first-phase insulin secretion.

For families concerned about metabolic health, the balance of macronutrients matters. This study found that a higher ratio of fat to carbohydrates in the diet was associated with lower insulin sensitivity and clearance in children. While this does not prescribe a specific diet, it suggests that monitoring the quality and ratio of fats and carbohydrates may be relevant for metabolic health, especially in African-American children who may have lower baseline insulin clearance.

Specific fiber-degrading bacteria (Akkermansia, Dialister, Oscillospira, Ruminococcaceae, Clostridiales) decrease in abundance with increasing BMI in Colombian and American populations.

If you are trying to improve your gut health through diet, focus on fiber intake. This study suggests that higher BMI is associated with lower levels of key fiber-degrading bacteria. Restoring these bacteria may require dietary changes that support their growth, rather than just probiotic supplements.

Long-term adherence to low-carbohydrate diets is associated with a significantly higher risk of all-cause mortality compared to high-carbohydrate diets.

If you are following a low-carbohydrate diet, be aware that current observational evidence suggests it may increase your risk of dying from any cause compared to diets higher in carbohydrates. This risk appears to be driven by the source of nutrients (e.g., animal proteins and fats vs. plant sources). Consider reviewing your diet's composition and consulting a healthcare provider to balance short-term metabolic benefits with long-term survival data.

Low-carbohydrate diets are not significantly associated with an increased risk of cardiovascular disease (CVD) mortality or incidence in the long term.

You do not need to worry that a low-carbohydrate diet will significantly increase your risk of heart disease or stroke based on current observational data. However, the source of your protein and fat (plant vs. animal) may influence these outcomes, so prioritize plant-based sources.

Increasing dietary intake of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) down-regulates the metabolic conversion of alpha-linolenic acid (ALNA) to longer-chain metabolites (EPA and DPA) in older men, whereas increasing ALNA intake does not up-regulate this conversion.

If you are trying to increase your long-chain omega-3s (EPA/DHA) by eating more plant-based sources (like flax or walnuts), understand that your body's conversion rate is very low and fixed. Increasing your intake of these plant fats will not significantly boost your EPA/DHA levels because your body does not up-regulate the conversion process. To effectively raise EPA/DHA, you must consume pre-formed sources (fatty fish or supplements), which may actually further suppress any minimal conversion from plant sources.

Increasing dietary EPA and DHA intake significantly reduces the metabolic conversion of alpha-linolenic acid (ALNA) to EPA and DPA in older men, demonstrating feedback inhibition of the desaturation/elongation pathway.

If you consume both plant-based omega-3s (ALNA) and fish oil (EPA/DHA), be aware that the fish oil will suppress your body's ability to convert the plant fats into long-chain omega-3s. Since the conversion rate is already very low, this suppression is likely negligible for your overall EPA/DHA levels, but it confirms that plant fats are not an efficient source of long-chain omega-3s when pre-formed sources are available.

Glutamine supplementation promotes M2 macrophage polarization via the glutamine-UDP-GlcNAc pathway and alpha-ketoglutarate production, which may help prevent obesity- or diabetes-associated pathology.

While glutamine is known to support immune health, this review highlights its specific role in shifting immune cells away from inflammation in obesity. Current research is mostly in mice, so humans should consult a doctor before using glutamine specifically for metabolic health, as the direct benefits in people are not yet fully proven.

Succinate accumulation, derived from glutamine-dependent anerplerosis, promotes M1 macrophage polarization and stabilizes HIF-1α, contributing to inflammation in obesity.

High levels of succinate are linked to inflammation in obesity. While you cannot directly 'take' succinate to fix this, understanding that it drives inflammation highlights why managing metabolic health is crucial. No specific succinate-based therapy is currently recommended for humans.

High-intensity exercise stimulates intramuscular triglyceride (IMTG) lipolysis, but the released fatty acids are not immediately oxidized; instead, they are released into the plasma and utilized during recovery.

During high-intensity exercise, your muscles break down stored fat (IMTG), but you don't burn it all right away. Some of this fat is released into your blood and used for energy during the recovery period after the workout.

Training with low carbohydrate availability ('train-low') enhances metabolic adaptations (e.g., mitochondrial enzyme activity) but does not improve performance compared to training with high carbohydrate availability.

If you are an endurance athlete, be aware that training with low carbs might change your metabolism, but it won't make you faster in a race. It is generally better to train with adequate carbohydrates to ensure you can perform at your best.

Frequent consumption of fungi and algae is associated with an increased prevalence of metabolic syndrome in Chinese men, whereas frequent consumption of nuts and pork is associated with a decreased prevalence in Chinese women.

For Chinese adults, dietary advice should be sex-specific. Men should monitor their intake of fungi and algae, as high frequency is linked to higher metabolic syndrome risk. Women may benefit from including nuts and pork in their diet, as high frequency is linked to lower risk. These findings highlight that 'healthy' foods may have different impacts based on sex.

Heterozygosity for the UCP3 exon 6-splice donor-stop polymorphism reduces basal fat oxidation by 50% and increases the respiratory quotient, indicating a metabolic shift toward carbohydrate oxidation and fat storage.

If you carry this specific UCP3 genetic variant, your body is genetically predisposed to burn less fat and store more carbohydrates at rest. This does not mean you are doomed to obesity, but it suggests that managing carbohydrate intake and maintaining physical activity to stimulate fat oxidation may be more critical for you than for someone without this variant. Focus on dietary patterns that support metabolic flexibility.

Administration of specific probiotics, such as Lactobacillus johnsonii N6.2, can hinder the development of diabetes in susceptible models by regulating gut integrity and modulating tight junction proteins like claudin-1.

If you have a genetic predisposition to diabetes or gut issues, maintaining gut barrier integrity is crucial. While this paper highlights Lactobacillus johnsonii N6.2 as a potential helper in animal models, it emphasizes that personalized nutrition and microbiome manipulation are key. Focus on a diet that supports your specific microbiome rather than relying on a single supplement.

Fecal microbiota transplantation (FMT) from lean, insulin-sensitive donors can significantly improve insulin sensitivity in insulin-resistant obese men within 6 weeks.

FMT from lean donors shows promise for improving insulin sensitivity in obese men, but it is not a guaranteed fix for everyone. This is a complex medical intervention. Current evidence suggests that dietary changes and lifestyle modifications are more accessible and foundational steps to support a healthy microbiome.

Soybean-oil-based lipid emulsions increase the risk of infection and sepsis in critically ill patients compared to lipid-free or alternative lipid formulations.

Be cautious with traditional soybean-oil-based lipid emulsions in septic or trauma patients, as they may increase infection risk. Consider alternative lipid emulsions (e.g., containing olive oil, MCT, or fish oil) which may have less impact on immune function.

Lipid emulsions rich in medium-chain triglycerides (MCT) or olive oil reduce oxidative stress and lipid peroxidation compared to soybean-oil-based emulsions.

If oxidative stress is a concern, consider using lipid emulsions containing MCT or olive oil, possibly supplemented with vitamin E, as they may cause less lipid peroxidation than traditional soybean-oil-based emulsions.

Adherence to a low carbohydrate-high protein diet is associated with increased total and cardiovascular mortality in women, particularly those aged 40-49 at baseline.

If you are a woman considering a low-carb, high-protein diet for long-term weight management, be aware that this specific dietary pattern is linked to higher risks of dying from heart disease and other causes. The benefits for short-term weight loss may come at the cost of long-term survival, especially if you are in your 40s.

High dietary intake of omega-6 polyunsaturated fatty acids (specifically linoleic acid) is positively associated with an increased risk of breast cancer, particularly in individuals with specific genetic variants affecting omega-6 metabolism.

If you have a family history of breast cancer or genetic risks, consider reducing high-omega-6 oils (corn, soybean, sunflower) and increasing omega-3 sources. This may help mitigate risk, especially if you have genetic variants affecting fat metabolism.

High protein-to-carbohydrate (P:C) ratios shorten lifespan in insects, potentially via TOR pathway activation, while low P:C ratios extend lifespan via AMPK activation, unless obesity ensues.

In insects, high protein shortens life via TOR, and low protein extends life via AMPK, but too little protein causes obesity. For humans, this implies a 'Goldilocks' zone for protein: too high may accelerate aging, too low may cause obesity, and the optimal balance is likely species-specific.

Globalization and economic policies favoring cheap fats, sugars, and fast food create an 'obesogenic environment' that drives obesity and diabetes rates, particularly among low-income populations.

Healthy food is often more expensive and less available than processed food due to global economic policies. Focus on community-level advocacy for better food access and policy changes, as individual choices are constrained by these systemic factors.

There is no definitive evidence that specific foods or drinks (e.g., fat, coffee, alcohol) consistently cause or prevent GERD symptoms across all populations.

Don't obsess over avoiding specific foods like coffee or fat unless you personally notice they trigger your symptoms. The evidence is mixed, and blanket restrictions are not supported by definitive data. Focus on weight loss first.

Shifting from red meat (cow/sheep) to white meat (pigs/poultry) without reducing total meat consumption yields minimal health benefits compared to reducing total meat and dairy.

Simply swapping beef for chicken or pork offers only modest health benefits. To make a significant difference in your heart health and cancer risk, you need to reduce your overall meat and dairy intake and replace it with more fruits, vegetables, and grains.

Adipose tissue hypoxia initiates a local inflammatory response that is necessary for angiogenesis and the maintenance of a healthy adipose microenvironment during expansion.

Understanding that inflammation is part of the body's attempt to support expanding fat tissue (via new blood vessels) may help contextualize why 'anti-inflammatory' approaches might not work for weight loss.