Posted on Dec. 30, 2005, 8:01 p.m. in Minerals
Selenium is an essential trace element found in organ meats, tuna, seafood, brewer’s yeast, fresh garlic, mushrooms, wheat germ, and some whole grains
ROLE IN ANTI-AGING:
Selenium is necessary for the body’s growth and protein synthesis. It helps to increase effectiveness of vitamin E, and acts as an antioxidant to protect cells from the free radical damage that causes aging and is linked to many age-related diseases. Results of two 5-year-long studies at Cornell University and the University of Arizona revealed that taking just 200 mcg of supplementary selenium each day cut the incidence of prostate cancer by 63%, colorectal tumors by 58%, and lung cancer by 46%. Altogether, the death rate from cancer of people who took 200mcg of selenium was found to be 39% lower than that of the general population. Selenium may help to prevent heart disease by increasing levels of "good" HDL cholesterol and lowering levels of "bad" LDL cholesterol, and reduce heart attack and stroke risk by decreasing the "stickiness" of the blood, and therefore reducing the risk of blood clots. Results of research published in 2001 revealed that people with the highest intake of selenium were 50% less likely to have asthma, compared with those who consumed the least.
Low selenium levels have also been linked to an increased risk of prostate cancer. Selenium also protects against toxic pollutants for sexual reproduction, helps to eliminate arsenic, and protect against the effects of cadmium and mercury. The mineral is also a component of glutathione peroxidase, which protects tissues from the effects of polyunsaturated fatty acid oxidation. Studies suggest that selenium and glutathione may play a key role in slowing the spread of HIV infection in the body. Research has shown that selenium can help to alleviate hot flushes and other symptoms of the menopause.
Dandruff, decreased growth, premature aging, infertility, and increased risk of cancer and heart disease. Infant deaths have also been associated with selenium and/or vitamin B deficiency,
THERAPEUTIC DAILY AMOUNT:
The RDA of selenium is 55mcg, however many experts recommend a daily intake of 100-200mcg.
MAXIMUM SAFE LEVEL:
The maximum safe level is 200mcg for longterm usage and 700mcg for short-term usage. Supplementation at levels greater than 800 mcg a day may be toxic. The Food and Nutrition Board states that overt selenium toxicity may occur in humans ingesting 2,400-3,000mcg
Side effects are rare, but can include dizziness, nausea, brittle fingernails, and hair loss.
SOLUBILITY:Insoluble in water