Selenium To Prevent Prostate Cancer? More Answers Needed

Tuesday, December 04, 2007

ROCHESTER, Minn. — A mineral diet supplement that lowers the risk of prostate cancer by 50 percent?

While there's no definitive proof, scientists are intrigued about the connection between prostate cancer risk and selenium, according to the December issue of Mayo Clinic Health Letter.

Selenium is a trace mineral that's essential to good health. While it's not an antioxidant, selenium is an element in the synthesis of proteins to make antioxidant enzymes. It is found in foods including nuts, meats, fish, poultry, eggs, dairy and whole grains. Typically, diet alone provides more than the Recommended Dietary Allowance of 55 micrograms (mcg).

Interest in the selenium and prostate cancer connection spiked in 1996 because of a surprise finding in a skin cancer study. Male participants took 200 mcg of selenium every day. Compared to men taking the placebo, the men taking selenium were found to have 63 percent fewer cases of prostate cancer. Two years later, the rates of prostate cancer remained 49 percent lower than the control group.

Though interesting, the results aren't conclusive and don't address possible risks from selenium supplements. A small study published this year indicated that taking 200 mcg of selenium daily may increase the risk of diabetes by 50 percent.

A large National Health Institute study looking at the benefits and risks of selenium supplements is under way and is projected to end in 2013. For now, selenium supplements aren't recommended as a preventive measure for prostate cancer. Regular screening tests remain the best way to detect prostate cancer.

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