Browse the evidence

Biofortification of staple crops (e.g., Golden Rice) with provitamin A carotenoids effectively prevents vitamin A deficiency and associated blindness in populations reliant on starch-based diets.

For populations dependent on staple crops, biofortified varieties like Golden Rice offer a sustainable solution to prevent vitamin A deficiency. This is a public health intervention rather than an individual dietary choice.

Folate deficiency causes extensive incorporation of uracil into human DNA, leading to chromosome breaks and increased colon cancer risk.

If you do not consume enough folate-rich foods (leafy greens, legumes), consider a multivitamin or folate supplement. This is especially important if you have a genetic variant (MTHFR) that affects folate processing, as this can increase your risk of DNA damage and colon cancer.

Dietary self-report instruments (FFQs and 24-hour recalls) significantly underestimate sodium intake (by 23-52% for FFQs and 23-28% for 24HRs), whereas potassium intake is captured with much higher accuracy (underreporting of only 5-6% for FFQs).

If you are tracking sodium for health reasons, do not rely solely on your memory or standard food diaries, as you will likely underestimate your intake by 25-50%. To get a more accurate picture, use multiple 24-hour recalls (averaging 3 is best) or focus on the Sodium:Potassium ratio, which is measured more accurately than sodium alone. For potassium, self-reports are reasonably accurate.

Magnesium acts as a physiological calcium antagonist and is involved in over 600 enzymatic reactions, making it essential for cellular physiology.

Magnesium is not just a supplement; it is a critical mineral involved in hundreds of body processes, from energy production to muscle function. Ensuring adequate intake supports these fundamental biological functions.

There is no global consensus on optimal vitamin D status, with definitions of deficiency and insufficiency varying significantly between organizations, leading to inconsistent prevalence estimates.

Be aware that 'vitamin D deficiency' and 'optimal levels' are defined differently by various health organizations. This makes it difficult to compare studies and determine a single 'perfect' blood level for everyone.

Subgroup analyses suggesting benefits from specific vitamins (e.g., Vitamin B6 for cardiovascular death, Vitamin E for myocardial infarction) were artifacts of trials funded or supplied by the pharmaceutical industry and disappeared in high-quality trials.

Be skeptical of claims that specific vitamins like B6 or E prevent heart attacks or death. This analysis shows these benefits only appear in studies funded or supplied by the pharmaceutical industry. When looking at high-quality, independent trials, these benefits disappear.

Hip circumference is a poor proxy for trunk fat and a good proxy for leg fat and lean mass, making waist-to-hip ratio (WHR) a complex metric influenced by both harmful trunk fat and protective leg tissue.

Use waist circumference to monitor abdominal fat, but understand that hip size reflects leg muscle and fat. A high WHR might mean high trunk fat OR low leg mass. DXA scans provide the clearest picture.

Urolithin A extends lifespan and improves muscle function in preclinical models by activating mitophagy and reducing inflammation.

This node describes animal studies. While it confirms the biological plausibility of UA's benefits, it does not directly translate to a human dosing protocol. It supports the use of UA in humans as described in Node 1.

Aging is associated with a significant increase in intramuscular noncontractile (fat) content and a decrease in contractile cross-sectional area, resulting in a >2-fold increase in fat relative to muscle mass in older adults compared to young adults.

As you age, your muscles naturally lose contractile tissue and gain fat, roughly doubling the fat content in your leg muscles. This is a primary driver of strength loss. While you cannot fully reverse aging, understanding this shift highlights why maintaining activity is critical for preserving muscle quality.

Chronic metabolic stress from aging and high-fat feeding causes systemic carnitine insufficiency, characterized by reduced skeletal muscle free carnitine levels and compromised mitochondrial fuel switching.

Aging and chronic overeating can deplete your body's natural carnitine stores, particularly in muscle. This depletion impairs your mitochondria's ability to switch between burning fat and sugar efficiently, contributing to insulin resistance.

Age-associated NAD+ decline is driven by two converging mechanisms: decreased biosynthesis (specifically reduced NAMPT expression) and increased consumption (specifically elevated PARP and CD38 activity due to DNA damage and aging).

NAD+ levels drop with age because your body makes less of it (due to lower NAMPT enzyme levels) and uses it up faster (due to DNA repair demands via PARP and other enzymes). This dual decline impairs cellular energy and repair mechanisms.

Long-term supplementation with beta carotene (50 mg on alternate days) provides no benefit and causes no significant harm regarding the incidence of malignant neoplasms, cardiovascular disease, or all-cause mortality in healthy, well-nourished men.

Do not take beta carotene supplements to prevent cancer or heart disease. This study of over 22,000 men followed for 12 years shows that taking 50 mg of beta carotene every other day does not reduce your risk of cancer, heart disease, or death compared to taking a placebo. While eating fruits and vegetables rich in beta carotene is beneficial, the isolated supplement offers no such protection.

Daily supplementation with 2000 IU of vitamin D3 does not reduce the incidence of invasive cancer or major cardiovascular events in adults aged 50+ (men) and 55+ (women) compared to placebo.

Taking 2000 IU of vitamin D3 daily will not prevent cancer or heart attacks in generally healthy older adults, according to this major study. While vitamin D is essential for bone health, this specific dose does not offer the broad disease-prevention benefits often marketed. Focus on proven strategies for cancer and heart health prevention rather than relying on this supplement for those outcomes.

Vitamin D3 supplementation (2000 IU/day) does not reduce all-cause mortality in adults aged 50+ (men) and 55+ (women).

Taking 2000 IU of vitamin D3 daily will not help you live longer, based on this study. While it may support bone health, it does not appear to extend lifespan in older adults who are generally healthy.

There is no highly convincing evidence of a clear role of vitamin D for any health outcome, as observational associations often fail to replicate in randomised controlled trials.

Do not expect Vitamin D supplements to prevent chronic diseases like cancer, heart disease, or diabetes based on current high-quality evidence. It is important for basic health, but supplementation for disease prevention is not strongly supported.

Supplementation with 1 g/day of marine n-3 fatty acids (containing 840 mg EPA/DHA) does not reduce the incidence of major cardiovascular events or invasive cancer in a general population at usual risk.

Taking 1 gram of fish oil daily (providing 840mg EPA/DHA) does not significantly lower your risk of heart attacks, strokes, or cancer if you are otherwise at average risk. Focus on proven lifestyle factors instead.

Low-dose supplementation with marine n-3 fatty acids (EPA-DHA) or plant-derived alpha-linolenic acid (ALA) does not significantly reduce the rate of major cardiovascular events in patients who have had a myocardial infarction and are receiving state-of-the-art standard therapy.

If you have had a heart attack, taking low-dose fish oil (EPA-DHA) or flaxseed oil (ALA) supplements will not significantly lower your risk of another major cardiovascular event, provided you are already taking your prescribed heart medications (blood pressure, blood thinner, and cholesterol drugs). Do not rely on these supplements as a substitute for standard medical therapy.

Vitamin D3 supplementation at 4000 IU/day does not significantly reduce the risk of developing type 2 diabetes in adults at high risk who are not selected for vitamin D insufficiency.

If you are at high risk for type 2 diabetes, taking 4000 IU of Vitamin D3 daily will not significantly lower your risk of developing the disease unless you are severely deficient. Focus on proven lifestyle changes like weight management and physical activity instead of relying on this supplement for prevention.

Supplementation with synthetic vitamins and antioxidants does not reduce the risk of major cardiovascular events in primary or secondary prevention.

Do not rely on vitamin or antioxidant supplements to prevent heart disease or stroke. This meta-analysis of nearly 300,000 participants found no benefit for major cardiovascular events. Focus on a diet rich in natural fruits and vegetables instead, as the study explicitly notes these findings do not apply to natural food sources.

Dietary polyphenol supplementation generally fails to produce significant anti-oxidative or anti-inflammatory effects in patients with metabolic syndrome, despite theoretical benefits.

Do not rely on polyphenol supplements to reduce inflammation or oxidative stress if you have Metabolic Syndrome. The evidence shows these supplements generally do not significantly improve these specific markers in humans, even if they help with weight or blood pressure. Focus on whole dietary patterns like the Mediterranean diet instead.

Long-term vitamin D supplementation does not reduce the risk of major adverse cardiovascular events (MACE), myocardial infarction, stroke, or all-cause mortality compared to placebo.

Based on this large meta-analysis, taking vitamin D supplements will not protect you from heart attacks, strokes, or early death, even if you have low levels. It is not indicated for cardiovascular prevention.

Olive oil polyphenols do NOT currently have sufficient evidence to support a health claim for maintaining normal blood HDL-cholesterol concentrations, despite some studies showing increased HDL levels.

Don't rely on olive oil to boost your HDL cholesterol as a primary heart health strategy. While some studies show HDL levels go up, regulators say this isn't a proven cause-and-effect benefit. Focus instead on the proven benefit: protecting your blood lipids from oxidation by using high-polyphenol olive oil as part of a healthy diet.

Supplementation with antioxidant vitamins (E, C, beta-carotene) fails to provide cardiovascular protection and may increase mortality or fatal CHD risk in large clinical trials.

Do not rely on high-dose antioxidant supplements (Vitamins E, C, Beta-Carotene) to prevent heart disease. Large clinical trials show they offer no benefit and may increase mortality risk. Focus on obtaining antioxidants from whole foods like fruits, vegetables, and whole grains instead.

Long-term use of single antioxidant supplements (Vitamin E, Beta-carotene) does not prevent cardiovascular disease and may increase the risk of certain adverse events.

Do not take single antioxidant supplements (like Vitamin E or Beta-Carotene) to prevent heart disease. Large studies show they do not work and may even be harmful. Focus on getting antioxidants from a healthy diet instead.