The prostate is a small gland that surrounds a portion of the male urethra and makes fluid that is part of semen. Several disorders originate in the prostate, including prostate cancer. The American Cancer Society reports that over 280,000 new cases of prostate cancer will develop in 2011 and that one man in six will develop the disease at some time. Some research observations suggested that taking selenium along with vitamin E might help prevent prostate cancer. However, recent results of a large clinical trial are less encouraging.
Selenium
Selenium is a trace mineral you obtain from your diet, especially from whole grains, meats, seafood and nuts. It is a potent antioxidant that helps remove free radicals from your body, which are metabolic byproducts that may damage cellular DNA and other cellular components. According to Memorial Sloan-Kettering Cancer Center, selenium is an important cancer preventive that may help protect you from gastrointestinal, lung and bladder cancer. It may also help lessen side effects of chemotherapy drugs and reduce intestinal upset caused by radiation therapy.
Vitamin E
Vitamin E is an important vitamin that is also a very strong antioxidant. Green leafy vegetables, eggs, wheat germ and whole grains provide lots of vitamin E. Chemically, only one form of vitamin E, called the d-isomer or d-alpha-tocopherol, has significant biological activity in humans. Vitamin E has many health benefits, such as boosting the immune system and slowing progression of some disorders, including macular degeneration in the retina and Parkinson's disease. Vitamin E may also lower the risk for certain cancers by enhancing your immune system's ability to detect and destroy abnormal, potentially cancerous cells.
The Prostate Cancer Trial
Because laboratory and animal research suggested that combining vitamin E and selenium might prevent prostate cancer, in 2001 the National Cancer Institute began a clinical trial of the two supplements as potential chemopreventives for prostate cancer. For the study, called the Selenium and Vitamin E Cancer Prevention Trial, or SELECT, over 35,000 older male subjects took either selenium, vitamin E, both selenium and vitamin E or a placebo for seven years. In 2008, the trial was halted and the results published in the "Journal of the American Medical Association". Researchers found that those who took selenium or selenium plus vitamin E had similar cancer rates as those who took the placebo; those who took vitamin E alone had slightly higher rates. A later study published in 2011 in the "Journal of Clinical Oncology," found that a similar regimen involving vitamin E and selenium did not prevent progression of a precancerous prostate condition to cancer.
Recommendations
Although data on vitamin E and selenium do not support their combined use to prevent prostate cancer, they are nevertheless beneficial for general health. Both are considered safe supplements, although vitamin E may interact with blood thinning medications. Do not take vitamin E if you have a family history of hemorrhagic stroke, and discuss both vitamin E and selenium with your doctor before adding either or both to your regimen.
References
- National Kidney and Urologic Diseases Information Clearinghouse: What I Need to Know About Prostate Problems
- American Cancer Society: Prostate Cancer
- "Journal of the American Medical Association"; Effect of Selenium and Vitamin E on Risk of Prostate Cancer and Other Cancers; S. Lippman, et al.; December 2008
- Memorial Sloan-Kettering Cancer Center: Selenium
- Memorial Sloan-Kettering Cancer Center: Vitamin E
- "Journal of Clinical Oncology"; Progression from High-Grade Prostatic Intraepithelial Neoplasia to Cancer: A Randomized Trial of Combination...; N. Fleshner, et al.; June 2011
