Image for selenium Selenium is an essential trace mineral that acts as an antioxidant —a substance that protects the body's cells against the effects of free radicals. Free radicals are normal by-products of metabolism, but they can cause cell damage.

Selenium's functions include:

  • Acting as a co-factor for the antioxidant enzyme glutathione peroxidase
  • Stimulating immune function
  • Ensuring proper function of the thyroid gland
  • Aiding cell growth