TargetedFoundationsVegan form available
Selenium
European soils are selenium-poor; 1–2 Brazil nuts a day cover it. As a supplement the window is narrow: 55 µg is good, above 200 µg raises diabetes risk.
3/5· Multiple human trialsEstimated monthly cost: ≈ 3 €
Dose
55–100 µg (selenomethionine) or 1–2 Brazil nuts.
Timing
Any time.
⚠ Cautions
Toxic above 400 µg (hair loss, brittle nails). Don't stack from several sources.
What it is
The trace element of glutathione peroxidase and thyroid deiodinases.
What the evidence shows
SELECT (n=35,533): 200 µg selenium didn't protect against prostate cancer and raised type 2 diabetes risk. In Hashimoto's, 200 µg lowered antibodies (small RCTs).
Goals
Immunity
Last reviewed: 6 September 2026
This site is educational and does not replace medical advice. Start any supplement or drug only after consulting a doctor or pharmacist.