Mineral
Selenium (as Fermented Selenium Glycinate)
Also known as: Selenium glycinate, Chelated selenium, Organic selenium
Selenium is an essential trace mineral incorporated into selenoproteins that provide antioxidant defense and thyroid hormone metabolism. Glycinate chelation may improve absorption compared to inorganic forms.
Primary uses
- Antioxidant defense
- Thyroid hormone metabolism
- Immune support
- Reproductive health
How it works
- Component of glutathione peroxidase and thioredoxin reductase
- Selenoprotein synthesis
- Thyroid peroxidase cofactor
- Free radical neutralization
Dosage
- Typical range
- 50-200 mcg daily
- Timing
- Consistent daily timing recommended
- With food
- Can be taken with or without food
- Duration
- Ongoing supplementation recommended; upper limit generally 400 mcg/day
- Special populations
- RDA: 55 mcg (adults), 60 mcg (pregnant), 70 mcg (lactating), 20-40 mcg (children). Upper limit: 400 mcg/day to avoid selenosis.
Forms
- Selenium glycinate (chelated form)· 70/100
Safety
Common side effects
- Garlic odor on breath
- Nausea at high doses
Contraindications
- History of selenosis
- Excessive iodine intake combined with high selenium (may worsen thyroid dysfunction)
Evidence notes
Strong RCT evidence supports selenium's role in antioxidant defense and thyroid health. Organic/chelated forms show improved bioavailability in comparison studies.
Grade A: Multiple well-designed human trials support the main claims.
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