Immune

Periconceptional folic acid prevents most neural tube defects — the single clearest reason to take it, and the myth-clearing reason it has to be folic acid, not 5-MTHF.

HEPA air purifiers are a well-established, evidence-backed tool for reducing airborne allergens and particulate matter indoors — direct relief of allergy and asthma symptoms is plausible but less consistently supported.

Corrects iron-deficiency anemia with some of the most reliable evidence in nutrition — but only if you're actually deficient. No proven energy benefit if you're not, and overdose is a real risk.

An antioxidant essential for immune function, collagen synthesis, and iron absorption — the immune benefit is modest and most reliable for shortening colds under heavy physical stress.

The sunshine vitamin most indoor-dwellers are low in — strong evidence for bone health and immune function, reasonable for energy.

Specifically the aged (Kyolic-style) form of garlic with several RCTs showing modest but real reductions in blood pressure and cholesterol.

The first-milk supplement TikTok says fixes your gut, skin, and immunity — real RCT evidence backs only two narrow uses: fewer respiratory infections in athletes, less diarrhea in kids.

Cold water immersion has decent evidence for reducing post-exercise soreness and inflammation, but the hype often outpaces what the science actually supports.

Decent trial evidence for shortening a cold or flu once you're sick — weak evidence it prevents one, and no legitimate claim to COVID-19 protection.

The body's most abundant amino acid with strong evidence for gut barrier integrity and immune support in stressed populations, but less clear benefit for healthy people.

N-acetyl cysteine is a glutathione precursor with strong evidence for liver protection and respiratory support, backed by decades of clinical use.

Live microorganisms with real evidence for specific gut conditions — but strain specificity matters enormously, and most products don't tell you enough.

A flavonoid with decent anti-inflammatory and immune evidence, plus emerging senolytic interest when paired with dasatinib.

An essential trace mineral critical for thyroid function and antioxidant defense — beneficial for those with low selenium status, but excess carries risk.

An essential trace mineral with good evidence for immune support — most people get enough from food, but certain groups benefit from supplementation.

A medicinal mushroom with centuries of traditional use and interesting mechanistic data, but limited rigorous human evidence for immune and sleep claims.

An essential fat-soluble vitamin for vision, immune function, and skin integrity — most people get enough from food, but deficiency remains a global health concern.