Selenium

Also known as: selenium methionine, selenomethionine, selenium yeast

Grade B — Moderate Evidencemineraltraceantioxidant

Recommended Dosage

100–200 mcg

With food. Do not exceed 400mcg/day.

Essential trace mineral for thyroid function (T4→T3 conversion) and antioxidant defense. Reduces Hashimoto's antibodies.

🛡️Immunity🧬Longevity✨Skin & Hair
Last reviewed: 2026-03-09

Evidence Rating: Grade B — Moderate Evidence

Some RCTs with positive results, or strong observational evidence. More research may refine our understanding.

Interaction Warnings

Blood thinnersLow

High doses may increase bleeding risk

Vitamin C (selenite form)Low

May reduce selenite absorption; less relevant with selenomethionine

⚠️ Important Notes

  • Do not exceed 400mcg/day — selenosis risk
  • Brazil nuts: 1-2/day often sufficient (70-90mcg/nut)
  • Narrow therapeutic window

Clinical Evidence (3 studies)

Selenium and human health

Rayman MP (2012) — Lancet

Comprehensive review: thyroid, cancer, cardiovascular, immune benefits

View on PubMed

Selenium reduced TPO antibodies in Hashimoto's

Gärtner R et al. (2002) — J Clin Endocrinol Metab

200mcg/day significantly reduced TPO antibodies

View on PubMed

Meta-analysis of selenium in Hashimoto's thyroiditis

Toulis KA et al. (2010) — Thyroid

4 RCTs: consistent TPO-Ab reduction

View on PubMed

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Grade B — Moderate Evidence

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Zinc

Grade A — Strong Evidence

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Astaxanthin

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⚕️ Important Disclaimer

This information is for educational purposes only. It is not medical advice. Always consult a healthcare provider before starting any supplement regimen, especially if you take medications or have health conditions.

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