Browse the evidence

Calcium supplementation reduces fracture risk in populations with low baseline calcium intake, but provides no additional skeletal benefit or fracture reduction in populations with adequate or high customary intake.

If you do not consume enough calcium-rich foods (like dairy, fortified alternatives, or leafy greens) to reach about 400-500 mg per day, supplementation can help reduce your risk of hip fractures. However, if you already eat a diet rich in calcium, adding more supplements will not further protect your bones or reduce fracture risk. Focus on dietary sources first.

Vitamin D supplementation, particularly when combined with calcium, reduces hip and non-vertebral fracture risk in elderly institutionalized populations, likely through improved neuromuscular function rather than solely bone mineral density changes.

For elderly individuals, especially those in care facilities or with limited sun exposure, daily supplementation with 800 IU of Vitamin D and 1200 mg of Calcium significantly reduces the risk of hip and other fractures. This benefit appears to come partly from improved muscle function and balance, not just stronger bones.

Alpha-linolenic acid (ALA) does not effectively substitute for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in preventing chronic diseases because human conversion of ALA to EPA and DHA is highly inefficient.

If you do not eat fatty fish, eating flax or walnuts (ALA) will not fully protect your heart or brain because your body converts very little of it into the active forms (EPA/DHA). To get the proven benefits of long-chain omega-3s, you should consume marine sources directly or take a fish/algal oil supplement, rather than relying solely on plant oils.

Daily supplementation with vitamin D (400-800 IU) combined with calcium (1000-1200 mg) reduces the risk of hip fracture by 16% in older adults, whereas vitamin D alone provides no significant fracture protection.

If you are an older adult looking to prevent hip fractures, taking Vitamin D alone is likely ineffective. You should take a daily combination of Vitamin D (400-800 IU) and Calcium (1000-1200 mg). This specific combination has been shown to significantly reduce hip fracture risk, whereas Vitamin D by itself does not.

Higher blood concentrations of 25-hydroxyvitamin D (25[OH]D) are associated with lower risks of fracture in observational studies, but this association is not replicated when using vitamin D supplementation alone in randomized trials.

Don't rely on Vitamin D alone to protect your bones. While people with naturally high Vitamin D levels have fewer fractures, taking Vitamin D supplements by themselves does not reduce fracture risk. You need to combine it with Calcium to see benefits.

Consuming broccoli or glucoraphanin-rich sources provides health benefits primarily through the formation of sulforaphane, but efficacy depends on the bioavailability of the source and individual microbiome capacity to convert glucoraphanin to sulforaphane.

To get the most benefit from broccoli, focus on getting enough glucoraphanin. This means choosing broccoli varieties known to be high in this compound (like certain sprouts or specific hybrids) rather than just any generic head. If you take supplements, be aware that sulforaphane is unstable, so look for stabilized formulations. Your gut bacteria play a key role in converting the precursor to the active form, so individual results may vary.

Consumption of prebiotics (specifically inulin-type fructans) and probiotics reduces serum total and LDL cholesterol levels in hypercholesterolemic or dyslipidemic individuals.

Adding prebiotic fibers like inulin or probiotic-enriched foods to your diet can help lower bad cholesterol (LDL) and total cholesterol levels in people with high cholesterol.

Adults with coeliac disease adhering to a strict gluten-free diet for 8-12 years exhibit significantly higher plasma homocysteine levels and lower folate and vitamin B-6 status compared to the general population, indicating a poor vitamin status despite histological remission.

If you have coeliac disease and have been on a gluten-free diet for several years, do not assume your diet is nutritionally complete just because your intestines have healed. You are at higher risk for low folate and vitamin B6, which can raise homocysteine levels—a risk factor for heart disease. Ask your doctor to check your vitamin levels and consider dietary changes or supplementation to correct any deficiencies.

Oral L-carnitine supplementation reverses diet-induced mitochondrial dysfunction and improves glucose tolerance in obese, insulin-resistant states by restoring carnitine homeostasis and promoting acylcarnitine efflux.

If you have insulin resistance or are aging, your body may naturally deplete carnitine, leading to mitochondrial inefficiency. Supplementing with L-carnitine (300 mg/kg/day in rats, roughly 2-3g/day for humans) for several months can restore this balance, improve how your muscles handle sugar, and help clear metabolic waste products. This is most effective when combined with addressing the underlying cause of the depletion, such as a high-fat diet.

Omega-3 fatty acid supplementation and consumption increase adiponectin levels, particularly in individuals with low basal levels, improving metabolic and oxidative profiles.

Consider increasing your intake of omega-3 fatty acids through fish oil supplements or omega-3 rich foods like fish. This can significantly raise your adiponectin levels, especially if your baseline levels are low, leading to better lipid and glucose metabolism.

Industrial dry milling and nixtamalization processing of maize significantly alters its micronutrient profile, typically reducing vitamins and fiber while increasing calcium, thereby necessitating targeted fortification to prevent micronutrient malnutrition.

If you rely on maize as a staple, be aware that processing (milling, cooking) changes its nutritional value. Industrial processing often removes beneficial fibers and vitamins. To maintain health, ensure your maize products are fortified with essential vitamins and minerals, or consume a diverse diet to compensate for processing losses.

Nixtamalization (alkali processing) of maize improves the bioavailability of niacin and protein quality while increasing calcium content, making it nutritionally superior to unprocessed maize.

If you eat tortillas or arepas made from nixtamalized maize, you are getting better niacin and protein absorption than from raw corn. This traditional processing method is nutritionally beneficial.

Iron fortification of maize flour is a cost-effective strategy to prevent micronutrient malnutrition, provided the fortification program is implemented at an industrial scale with appropriate quality control.

For communities relying on maize, iron-fortified flour is a key tool to prevent anemia. Ensure that the maize flour you buy is from a reputable industrial source that adheres to fortification standards.

Mineral deficiencies (specifically Magnesium, Zinc, Iron, Copper, and Selenium) impair immune competence by disrupting innate and adaptive immune cell function and inflammation regulation, whereas maintaining adequate levels through a balanced diet supports optimal immune defense.

Focus on eating a varied diet rich in vegetables, nuts, seeds, whole grains, and lean proteins to naturally cover your mineral needs. You likely do not need supplements unless you are in an at-risk group (like an athlete with a restricted diet, elderly, or pregnant) or have a diagnosed deficiency. If you do supplement, do so under medical guidance to avoid toxicity, as too much of certain minerals (like Iron or Zinc) can actually harm your immune system or feed pathogens.

Magnesium deficiency promotes a pro-inflammatory state by increasing cytokine production (IL-6, TNF-alpha) and oxidative stress, while adequate Magnesium levels help regulate inflammation and support T-cell function.

If you have chronic low-grade inflammation, check your Magnesium levels. Ensuring adequate intake through foods like spinach, nuts, and seeds may help lower inflammatory markers like CRP. Do not self-prescribe high-dose supplements without testing, as balance is key.

Zinc supplementation (>75 mg/day) significantly reduces the duration of common colds, and adequate Zinc status is critical for T-cell maturation and preventing thymic atrophy, though excessive doses (>40 mg/day long-term) can cause immune dysfunction.

If you catch a cold, starting Zinc lozenges or supplements (totaling >75mg/day) within 24 hours may shorten the illness. Do not take high-dose Zinc (over 40mg/day) as a daily long-term supplement, as it can harm your immune system and cause other health issues. Get your Zinc from food sources like beef, oysters, and nuts instead.

Increased intake of omega-3 fatty acids (from fish or supplements) improves cardiometabolic health markers (blood pressure, triglycerides, inflammation, insulin sensitivity) in obese and metabolic syndrome patients, independent of weight loss.

Eat fatty fish or take omega-3 supplements to improve your heart health, lower triglycerides, and reduce inflammation. Do not expect this to cause weight loss on its own, but it will support your metabolic health.

Intravenous pretreatment with N-acetylcysteine (150 mg/kg) inhibits the development of fatigue in human skeletal muscle during low-frequency (10 Hz) electrical stimulation, increasing force output by approximately 15% compared to control.

This study demonstrates that a single high-dose intravenous injection of N-acetylcysteine (150 mg/kg) can reduce muscle fatigue during low-intensity, repetitive exercise in healthy men. However, this benefit comes with a high risk of unpleasant side effects (nausea, flushing, dizziness) requiring additional medication (diphenhydramine). Because the intervention requires IV administration and causes significant distress, it is not a practical or recommended strategy for improving exercise performance in healthy individuals. It serves primarily as evidence that oxidative stress contributes to fatigue.

High intake of trans fatty acids and Westernized diets (high in refined starches, sugar, saturated/trans fats) significantly increase systemic inflammation, evidenced by elevated C-reactive protein (CRP) and interleukin-6 (IL-6).

To lower inflammation, reduce intake of trans fats, refined sugars, and saturated fats found in processed foods, sweets, and fried items. Increase consumption of fruits, vegetables, legumes, fish, and whole grains, which are associated with lower levels of inflammatory markers like CRP and IL-6.

Omega-3 polyunsaturated fatty acids (PUFAs), specifically EPA and DHA, attenuate inflammatory responses to stressors and endotoxin challenges by inhibiting NF-kappaB activation and reducing proinflammatory cytokine production (TNF-alpha, IL-6).

Increase intake of omega-3 fatty acids (EPA and DHA) from fish, fish oil, walnuts, or supplements. These nutrients help reduce inflammation by inhibiting NF-kappaB activation and lowering proinflammatory cytokines, particularly in response to stress or unhealthy meals.

Obesity (BMI >= 30 kg/m2) significantly blunts the response to Vitamin D3 supplementation, resulting in serum 25-(OH)D levels approximately 17.8 nmol/L lower than in normal-weight women for the same dose.

If you are obese, standard Vitamin D doses (like 800 IU) may not be enough to reach optimal blood levels. You likely need a higher dose to overcome the sequestration of Vitamin D in fat tissue. Consult your doctor for a personalized dose, as you may need significantly more than the standard recommendation.

Direct supplementation with EPA and DHA is significantly more effective for cardiovascular health and raising the n-3 index than consuming alpha-linolenic acid (ALA) from plant sources, due to the extremely low and variable bioconversion rate of ALA to EPA/DHA in humans.

If your goal is cardiovascular protection or raising your blood omega-3 levels, direct sources of EPA and DHA (from fish or algae supplements) are far more effective than relying on plant sources like flax or chia seeds. Your body converts very little of the plant-based ALA into the active EPA and DHA needed for these benefits. Vegans should prioritize algae-based EPA/DHA supplements to ensure adequate intake.

Stearidonic acid (SDA) is a more effective plant-based precursor for increasing EPA levels than alpha-linolenic acid (ALA) because it bypasses the rate-limiting delta-6-desaturase enzyme step in the conversion pathway.

If you cannot take fish or algae oil, look for supplements containing Stearidonic Acid (SDA) from sources like Echium plantagineum or Buglossoides arvensis (Ahiflower). These provide more EPA than equivalent amounts of standard flax or chia oil because they skip the hardest step of conversion in your body.

Genetic variants in the FADS1-2-3 gene cluster significantly reduce the bioconversion of ALA to EPA/DHA, making direct EPA/DHA supplementation necessary for populations with high prevalence of these variants (e.g., Americans, East Asians).

If you are of American or East Asian descent, your body is genetically less efficient at converting plant omega-3s (flax/chia) into active forms. You should prioritize direct sources of EPA and DHA (fish or algae oil) to ensure you get the benefits, whereas South Asian or African populations may have better conversion efficiency from plant sources.