BALTIMORE, MARYLAND. There is growing evidence that certain micronutrients, more specifically antioxidants, may help prevent some forms of cancer. Selenium, for example, has been found highly effective in preventing prostate cancer. Researchers at the Johns Hopkins School of Public Health now report that gamma-tocopherol, the form of vitamin E found in most foods, is also effective in preventing prostate cancer. Their study involved over 20,000 male residents of Washington County, Maryland who had donated blood in 1974 and 1989. A total of 324 men had developed prostate cancer by 1996. These men were each matched with two healthy controls in regard to age, race, and date of blood donation. Comparing the blood levels of micronutrients in cases and controls found no significant differences in concentrations of alpha-carotene, beta-carotene, total carotene, beta-cryptoxanthin, lutein, lycopene, retinol, and ascorbic acid (vitamin C). There was, however, a difference in gamma-tocopherol levels between cases and controls with controls having significantly lower levels. For the men who donated blood in 1989 it was observed that men with the highest gamma-tocopherol levels had an almost 5 times lower incidence of prostate cancer than did those with the lowest levels. There was also some evidence that higher circulating levels of retinyl palmitate (formed from vitamin A and stored in the liver) were protective against prostate cancer. The researchers conclude that gamma-tocopherol may help protect against prostate cancer, but note that lycopene did not appear to have any protective effect.
Huang, Han-Yao, et al. Prospective study of antioxidant micronutrients in the blood and the risk of developing prostate cancer. American Journal of Epidemiology, Vol. 157, February 15, 2003, pp. 335- 44