Selenium (Selenomethionine)

Mineral

Cofactor for glutathione peroxidase and thyroid hormone activation. Two Brazil nuts per day already meet requirements; toxicity above 400 mcg.

thyroidantioxidantfertilityglutathione

Typical dose

100–200 mcg daily

Evidence

Moderate (some RCTs)

Onset time

Cumulative: 4–12 weeks

Half-life

~252 days (long body store)

Forms

Capsule, Tablet

Source

synthetic

Best taken with

with food

Best time of day

any

Bioavailability

5/5

Safety rating

3/5

Price per serving

$0.10

Vegan / GF / 3rd-party

✓ / ✓ / ✓

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Common uses

• Thyroid support
• Hashimoto's
• Antioxidant

Effect profile

Strength

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Muscle

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Energy

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Focus

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Mood

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Sleep

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Immunity

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Recovery

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Longevity

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Common side effects

• Selenosis (>400 mcg/day): hair loss, garlic breath, brittle nails

Avoid if

• Already eating Brazil nuts daily

Drug interactions

• Anticoagulants

Related mineral supplements

Selenium (Selenomethionine) vs Zinc Selenium (Selenomethionine) vs Iron Bisglycinate Selenium (Selenomethionine) vs Iodine (Potassium Iodide)

Medical disclaimer

SupplementDuel is for educational purposes only and is not medical advice. Consult a physician before starting, stopping, or combining supplements.