Selenium
Commonly used for
EnergyHealthy AgingHair Health
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The cheapest product is usually low quality, but more expensive doesn’t always mean better.
What is it? / Overview
Selenium supports antioxidant enzymes and thyroid hormone metabolism. Supplementation is most beneficial in individuals with inadequate intake or documented deficiency.
How is it used? / Administration
Form: Selenomethionine
Typical dose studied: 100–200 mcg/day
Timing: With food
Brazil nuts are a rich source but vary greatly in selenium content. Do not exceed upper limit.
What does it pair with?
Pairs well with:
Frequently combined as related antioxidant nutrients, but neither requires the other — Selenium-dependent enzymes and vitamin E both participate in antioxidant defense; commonly sold together, but not a strict requirement.
How well does it work? / Evidence
✓ Well-established
Who should avoid it?
Already taking it? Count intake from multivitamins to avoid excess -- stay under 400 mcg/day total from all sources.
Research & references
NIH ODS Selenium Fact Sheet. Rayman MP. Selenium and human health. EFSA Dietary Reference Values for Selenium.
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