Selenium for Thyroid Disorders
Selenium supports thyroid hormone metabolism and helps in autoimmune thyroiditis and mild Graves orbitopathy, but it is not a treatment for hypo- or hyperthyroidism.
Overview
Verdict
How It Works
Dosing & Protocol
Typical dose
- Recommended dose
- 200mcg daily
- Expected timeframe
- 3-6 months
Protocol
- form
- Selenomethionine or sodium selenite
- duration
- 6 months with thyroid function and antibodies rechecked
- co factor
- Take with a meal. Evidence is mixed because thyroid disorders is a broad category: selenium reduces TPO antibodies in Hashimoto thyroiditis and helps mild Graves orbitopathy, but does nothing for nodules, thyroid cancer, or hypothyroidism in selenium-replete people, and it does not reduce levothyroxine requirement.
- titration
- No escalation; keep total intake from food and supplements below 400 mcg/day
- starting dose
- 200 mcg selenium daily with food
Evidence
What the studies say
Effects of different supplements on Hashimoto's thyroiditis: a systematic review and network meta-analysis
The use of selenium supplements was able to significantly reduce the levels of thyroid peroxidase autoantibodies (TPOAb).
Selenium Supplementation in Patients with Hashimoto Thyroiditis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials
In people with HT without THRT, selenium was effective and safe in lowering TSH, TPOAb, and MDA levels.
Myo-inositol plus selenium supplementation restores euthyroid state in Hashimoto's patients with subclinical hypothyroidism
168 Hashimoto patients with TSH 3-6; myo-inositol plus selenium lowered TSH, TPOAb and TgAb more than selenium alone.
Effect of selenium on thyroid autoimmunity and regulatory T cells in patients with Hashimoto's thyroiditis: A prospective randomized-controlled trial
SYT treatment significantly decreased TPOAb, TGAb, and thyroid stimulating hormone (TSH) levels compared with the control group.
Safety
Caveats
Selenium does not replace levothyroxine or antithyroid drugs - never adjust prescribed treatment yourself. A thyroid lump, hoarseness, difficulty swallowing or rapidly enlarging goitre needs urgent assessment. Safety ceiling: the tolerable upper limit is 400 mcg/day from all sources, and two Brazil nuts can reach 200 mcg alone; chronic excess causes selenosis with hair and nail loss, garlic breath, nausea and neuropathy. Supplementation is associated with increased type 2 diabetes risk in replete populations. Take levothyroxine on an empty stomach, separate from supplements. Discuss with your obstetric team in pregnancy, where thyroid control is critical.
Less likely to help if
Medical Disclaimer
The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.
Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.