Mineral

Selenium (Selenomethionine)

Also known as: L-selenomethionine, Organic selenium

Evidence

Highly bioavailable organic selenium for thyroid and antioxidant function. Narrow optimal range requires careful dosing.

Primary uses

Thyroid support
Glutathione system
Immune function

How it works

Incorporated into selenoproteins
Essential for T4 to T3 conversion
Supports glutathione peroxidase

Dosage

Typical range: 100-200 mcg daily
Timing: Any
With food: Optional
Duration: Don't exceed 400 mcg
Special populations: Thyroid patients

Forms

Selenomethionine
Selenium yeast

Safety

Common side effects

Garlic breath at high doses

Contraindications

High selenium status

Evidence notes

Well-established for thyroid and antioxidant

Grade A: Multiple well-designed human trials support the main claims.

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.