Selenium is a vital trace element nutrient with multiple roles in the growth and functioning of living cells in higher animals and humans. This element is unevenly distributed in the earth’s crust. Almost all of the selenium in animal tissue is found in the proteins. Some of these proteins contain stoichiometric quantities of selenium and are known as selenoproteins. Other proteins contain variable amounts of selenium (which substitutes sulfur randomly in the original protein) and are known as selenium-binding proteins.
Based on epidemiological data, a lower antioxidant status has been linked to higher incidence of cardiovascular diseases due to increased levels of LDL oxidation. Selenium is one of the antioxidants that may help to inhibit LDL oxidation