Selenium (Thyroid Support)
An essential trace mineral critical for thyroid hormone conversion and thyroid gland protection.
Also known as: Selenomethionine • Sodium Selenite • Se
Overview
Selenium is the most important mineral for thyroid function. The thyroid gland contains more selenium per gram than any other organ. Selenium-dependent enzymes (deiodinases) convert inactive T4 to active T3, while selenoproteins (glutathione peroxidase) protect the thyroid from oxidative damage caused by hydrogen peroxide produced during hormone synthesis.
Key Benefits
T4 to T3 Conversion
Deiodinase enzymes require selenium to convert inactive T4 to active T3 thyroid hormone.
Thyroid Gland Protection
Glutathione peroxidase neutralizes hydrogen peroxide produced during thyroid hormone synthesis.
Autoimmune Thyroid Support
Studies show reduced TPO antibodies in Hashimoto's thyroiditis with selenium supplementation.
Antioxidant Defense
Supports the body's glutathione system, the master antioxidant network.
Dosage & How to Take
100-200 mcg daily.
| Purpose | Dose | Notes |
|---|---|---|
| General thyroid support | 100-150 mcg/day | With food |
| Hashimoto's support | 200 mcg/day | As studied in clinical trials |
Best Time to Take
With food.
With or Without Food
Yes, with food.
Forms & Bioavailability
| Form | Absorption | Best For | Notes |
|---|---|---|---|
| Selenomethionine | High | Best absorbed organic form | Incorporated into body proteins. |
| Sodium Selenite | Moderate | Budget option | Inorganic form, less well retained. |
| Selenium Yeast | Good | Food-based form | Contains mixed selenium species. |
Side Effects & Safety
Common
- Generally well tolerated at recommended doses
Rare
- Garlic breath
- Brittle nails (at excess doses)
Contraindications
- Do not exceed 400 mcg/day (toxicity risk)
Interactions
May enhance thyroid hormone conversion; monitor levels.
Scientific Research
Selenium and Hashimoto's thyroiditis
Meta-analysis showed 200 mcg/day selenium significantly reduced TPO antibody levels in Hashimoto's patients.
Food Sources
Products With Selenium (Thyroid Support)
2 products in our database contain this ingredient
Frequently Asked Questions
Medical Disclaimer
This content is for educational and informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before starting any supplement regimen, especially if you have pre-existing health conditions or are taking medications. The statements on this page have not been evaluated by the Food and Drug Administration.