Antioxidant vitamin and mineral supplementation may help prevent prostate cancer

The use of antioxidant vitamin and mineral supplements is associated with a lower incidence of prostate cancer among men with normal prostate specific antigen (PSA) levels.

Dr. Francois Meyer from Laval University Cancer Research Center, Quebec City, colleagues assessed whether daily supplementation with antioxidant vitamins (vitamin C, vitamin E and beta-carotene) and minerals (selenium and zinc) reduced the occurrence of prostate cancer or influenced its biochemical markers.More than 5000 men were randomized to the supplements or placebo. Biochemical marker data were available at baseline and median follow-up of about 9 years for 3616 men.Supplementation was associated with a 48% reduction in the incidence of prostate cancer among men with a baseline PSA level below 3 micrograms/L, the authors report in the August 20th International Journal of Cancer.In contrast, men with a baseline PSA level of 3 micrograms/L or greater who took supplements experienced a 54% increase in the incidence of prostate cancer.Baseline vitamin C levels showed a similar pattern, the researchers note.Antioxidant vitamin and mineral supplementation had no clear impact on the levels of five biomarkers of prostate cancer, the report indicates."Our study results support the hypothesis that chemoprevention of prostate cancer can be achieved with antioxidant vitamins and minerals," the investigators conclude.They recommend additional trials "to identify the best preventative agent or combination of agents and to determine which dosages are both safe and effective."(Source: Int J Cancer 2005;116:182-186: Reuters Health: Oncolink: August 2005.)