Selenium is a strong antioxidant found in many natural sources, depending on how abundant the selenium concentration is in a region's soil. The soil in China, New Zealand and southeastern U.S. is particularly selenium-deficient. Some studies have shown selenium to be an effective supplement for preventing heart disease and cancer.
Natural Food Sources
Bran, broccoli, brown rice, cabbage, chicken, garlic, kidney, liver, milk, mushrooms, nuts (especially Brazil nuts), nutritional yeast, oatmeal, onions, seafood, whole grain products.
Selenium works in conjunction with vitamin E and is involved in several enzyme systems. It is necessary for healthy skin, muscles and heart function. Selenium promotes the formation of antibodies and can help prevent infection. It also helps prevent the absorption of metals such as mercury, silver and thallium and may protect against prostate cancer.
Selenium deficiency can lead to premature aging, muscular aches, nerve cell damage, mental retardation and infertility. It has even resulted in myocardial deaths.
More than 600 mcg can be toxic in adults, and much less in infants. Symptoms include nausea, diarrhea, abdominal pain, fatigue, sour-milk breath, tooth decay and hair loss.
Recommended Dietary Allowance
Men: 70 mcg
Women: 55 mcg