Selenium

Selenium (Se)

  • Definition/Function: Trace element essential for the activity of antioxidant enzyme glutathione peroxidase and the conversion of T4 → T3 via iodothyronine deiodinase.

  • Daily Requirement: ~55 µg/day (adult).

  • Deficiency: Causes Keshan disease (cardiomyopathy) and muscle pain/weakness.

  • Sources: Brazil nuts, seafood, meats, cereals.

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