High blood levels of the major vitamin E components, alpha- and gamma-tocopherol, seem to cut the risk of prostate cancer by about 50 percent each, a study shows.

The findings are based on an analysis of 100 individuals with prostate cancer and 200 cancer-free “controls” participating in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, which included nearly 30,000 Finnish men.

Men with the highest levels of alpha-tocopherol in their blood at baseline were 51 percent less likely to develop prostate cancer than those with the lowest levels, report investigators in this week’s Journal of the National Cancer Institute (NCI).

Similarly, men with the highest levels of gamma-tocopherol were 43 percent less likely to develop the disease compared with men with the lowest levels.

Further analysis showed that the link between high tocopherol levels and low cancer risk was stronger among subjects using alpha-tocopherol supplements than among non-users.

This supports the original findings from the ATBC study, which showed that daily vitamin E supplementation reduced the risk of prostate cancer by 32 percent.

Dr. Demetrius Albanes, from the NCI in Bethesda, Maryland, and colleagues believe that the antioxidant activity of vitamin E may be particularly important to the associations they observed in the current study because oxidative stress has been tied to the development of prostate cancer.

However, alpha-tocopherol has other non-antioxidant properties, such as enhancement of the immune response, which may also play a role in the benefits seen, they add.

SOURCE: Journal of the National Cancer Institute, March 2, 2005.