Organic Selenium Supplement Yeast Free An F.D.A. Regulated Facility Potency & Quality GuaranteedSelenium is an important trace mineral. It is essential to the function of Glutathione Peroxidase, an antioxidant enzyme, which neutralizes harmful peroxide free radicals. Muscle enzymes also use Selenium to maintain normal mass and tone.Each capsule contains Selenium organically-bound with L-Methionine, an essential amino acid in human nutrition.