They are unstable molecules that in their bid to become more stable must bump into healthy cells and cause damage.  Free radicals contribute to cardiovascular disease by producing oxidized LDL cholesterol, which causes atherosclerotic plaques.

Selenium’s antioxidant properties also help in cancer, which can result from free radicals damaging cellular genetic material.  It is believed to be an anti-aging vitamin because as an antioxidant it protects the body against environmental pollutants other substances that and lead to aging.

Selenium regulates fat metabolism by controlling the production of thyroid hormone. Selenium and vitamin E act together to produce the antibodies which are important for protecting the body from infections.  Selenium supplementation is particularly important for men because selenium concentrates in the testicles and is lost through seminal fluid.  Selenium, vitamin E and zinc have been shown to reduce prostate inflammation. Selenium has been used to treat many conditions including male infertility, asthma, arthritis, cataracts, AIDS, hypothyroidism, alcoholic cirrhosis and high blood pressure.

Selenium supplements are available in tablet or capsule form.  Selenium is often grown on yeast and may not be suitable for those who are sensitive to yeast or have a tendency towards candida infections.  Selenomethionine is another highly active form of selenium that does not contain yeast.  Selenium works well with vitamin E, vitamin C and beta-carotene and can often be found in a complex with these other antioxidants.

Selenium levels may be decreased by high dose corticosteroid therapy (prednisone).