Because it boosts the body's antioxidant capacity, selenium is thought to have some ability to control cell damage that may lead to cancer. Selenium may even act in other ways to stop early cancer cells in their development. A recent study also suggested that selenium may enhance immune function, at least in those healthy adults with relatively low blood selenium. So far based on the evidence of animal and epidemiological studies, the role of selenium and cancer is probably the most significant for prostate cancer.
Selenium and Prostate Cancer
Quite a few promising studies published in 2004 showed the potential benefits of selenium in prevention of prostate cancer. One particular epidemiological study published in May 2004 in the Journal of National Cancer Institute revealed that men with high blood levels of selenium were about half as likely to develop advanced prostate cancer as the men with lower blood selenium. This study had a good sample size (>1000 healthy male) and a long study period of over 13 years. The duration is significant because prostate cancer is a slow growing disease.
A well designed randomized double-blind controlled study would be able to determine selenium's benefits. Currently the SELECT trial (the Selenium and Vitamin E Cancer Prevention Trial) is in progress. This study hopes to enroll 32,000 men aged 55 or older and will be follow them for 12 years.
Selenium and other cancers
Several other studies recently suggested that lower blood selenium may be associated with increased risk of colon cancer. Another study published in August 2004 also revealed that selenium may prevent gastric cancer, especially in men.
Selenium Key Message: Enjoy the benefits of selenium! Selenium is found in many foods such as seafood, lean meats, grains, eggs and garlic. It is unknown that how much selenium is enough for men. In addition, we also don't know if selenium supplements help every man or only some. If you are taking a selenium supplement, the maximum amount from food and supplements considered safe is 400 mcg a day.
Information on this site is provided for informational purposes and is not meant to substitute for the advice provided by your own physician or dietitian. Information and statements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease.