Selenium is a nutritionally important mineral and a chemical element.

• scientific information
• nutritional information
• food sources
• excess

nutritional information:

    The nutritional importance of selenium was first identified in 1957.

    Selenium works as part of glutathione peroxidases and selenium-containing proteins. The selenium in glutathione peroxidases helps the body break down hydrogen peroxide into water (hydrogen peroxide is one of the most dangerous generators of free radicals).

    Selenium is crucial for the formation of thyroid hormones.

    Selenium helps maintain brain function and mental acuity in elderly persons.

    Selenium helps the body fight infections and helps prevent harmful mutations n coxsackie and influenza viruses.

IMPORTANCE: A major antioxidant nutrient, protects cell membranes and prevents free radical generation thereby decreasing the risk of cancer and disease of the heart and blood vessels.  Medical surveys show that increased selenium intake decreases the risk of breast, colon, lung and prostate cancer. Selenium also preserves tissue elasticity; slows down the aging and hardening of tissues through oxidation; helps in the treatment and prevention of dandruff.     DEFICIENCY SYMPTOMS: May result in premature aging, heart disease, dandruff, loose skin. —courtesy of Austin Nutritional research

    Selenium is a cancer-preventing antioxidant.

    A 2007 study showed that “low plasma selenium is independently associated with poor skeletal muscle strength in community-dwelling older adults in Tuscany.” That is, low selenium levels may cause muscle weakness. The study conducted by the Tuscany regional Agency (Florence, Italy), John Hopkins School of Medicine (Baaltimore, Maryland), Azienda Sanitaria Firenze (Florence, Italy), Laboratory of Epidemiology, Demography and Biometry, National Institute of Aging (Bethesda, Maryland), and Longitudinal Studies Section, Clinical Research Branch, Natinal Institute on Aging(Blatimore, Maryland) and published in the American Journal of Clinical Nutrition, Vol. 86, No.2, pages 347-352, August 2007.
    Sources of selenium include Brazil nuts, sesame seeds, legumes, and meat.

    Selenium helps the body detoxify mercury (a dangerous toxic metal).

    While it is best to obtain nutrients from natural foods, you can find dietary selenium in supplements in the form of selenomethionine, high-selenium yeast, selenium picolinate, selenium citrate, selenium aspartate, sodium selentie, and sodium selenate.

excesses:

    Excessive doses of selenium might be associated with increased risk of type 2 diabetes. The recommnded dose of selenium a day is 200-300 mcg per day. Up to 600 mcg a day to fight colds or flu is safe for short periods. Laarger doses should only be taken under the advice of a physician.

scientific information:

    Selenium is a non-metal related to sulfur and tellurium.

    Name: selenium

    Symbol: Se

    Atomic Number: 34

    Periodic Table: Group (or family) 16 (old European IUPAC system group VIB; old American CAS system group VIA), chalcogens; Period 4; p-block

    Atomic mass: 78.96(3) g/mol

See also: minerals

next mineral