Best for Hormones
Best Selenium for Hormones
Top 30 products ranked · Reviewed May 2026 · 100–200 mcg clinical dose
Why Selenium for Hormones
Selenium plays a supporting role in hormones. Essential component of selenoproteins including glutathione peroxidase (antioxidant defense) and deiodinases (thyroid hormone activation). Selenomethionine is the most bioavailable supplemental form, while sodium selenite is inorganic and less efficiently absorbed.
What dose to look for
Clinical studies typically use 100–200 mcg of selenium. Common supplement dose; UL is 400 mcg/day. Products below this range may not deliver meaningful results.
What form to look for
Avoid sodium selenite — inorganic, lower retention. Look for selenomethionine for better absorption.
What the research says
Selenium has moderate clinical evidence for hormones benefits. SELECT (n=35,533) showed no cancer prevention benefit and an INCREASE in type 2 diabetes risk. Essential thyroid cofactor in deficient populations; supplement only when intake is documented low Learn more
Clinical research on Selenium
MODERATE for anti-TPO antibody reduction in Hashimoto's — inconsistent on actual thyroid function · ~200 mcg/day (Hashimoto's contexts); stay at/below RDA otherwise (UL 400 mcg/day)
- •Pooled trials in Hashimoto's patients found modest reductions in anti-TPO antibody titers with 200 mcg/day over 3–6 months; effects on TSH and free T4 were small and inconsistent. PubMed
- •Anti-TPO antibody titer is a surrogate marker — it can drop without clinical thyroid function meaningfully changing, and long-term outcomes (progression to hypothyroidism) are undemonstrated.
- •Iodothyronine deiodinases that convert T4 to active T3 are selenoproteins, and the thyroid holds the body's highest tissue selenium — the mechanistic basis for the autoimmune-thyroid signal.
- •NPC trial secondary analysis: 200 mcg/day selenium increased incident type 2 diabetes, concentrated in those with the highest baseline selenium — a reason not to mega-dose in the replete. PubMed