Vanguard Neurologist

From MedWire News

People with a high intake of vitamin C-rich vegetables have a decreased risk of prostate cancer, although other vegetables and fruit do not greatly affect the risk of the disease, Australian study findings suggest.

It is believed that diet plays an important role in the incidence of prostate cancer, although studies so far have produced inconclusive results. However, specific bioactive compounds from plant foods have been shown to reduce prostate cancer risk.

To investigate further, Gina Ambrosini, from the University of Western Australia in Perth, and colleagues studied 1985 men who were previously exposed to asbestos and randomly assigned to receive 30 mg beta-carotene (or 0.75-30.0 mg if they had abnormal liver function tests) or 7.5 mg retinol supplements daily as part of a cancer prevention program.

In addition, the men completed a semi-quantitative food frequency questionnaire to assess average daily intakes of 43 foods during the previous year, the team reports in the journal Prostate Cancer and Prostatic Diseases.

During a median follow-up period of 12.7 years, 441 men died, there were 97 incident cases of prostate cancer, and 35 participants were lost to follow-up. Prostate cancer cases were significantly older than non-cases at baseline, at 62.6 years versus 54.7 years.

There were no overall differences in fruit and vegetable intake, although cases had significantly lower median intakes of cooked tomato, broccoli, and bell peppers. Multivariate analysis taking into account age and source of asbestos exposure revealed that vitamin A supplementation, total fruit, and vegetable intakes were not associated with prostate cancer.

However, increasing intakes of vitamin C-rich foods, such as peppers, broccoli, and spinach, were associated with a lower risk of prostate cancer, with men in the highest tertile of intake having a relative risk of prostate cancer of 0.53 versus the lowest intake.

The team concludes: “Prostate cancer risk in this study does not appear to be strongly associated with the intake of beta-carotene, retinol, fruits or vegetables, except possibly with vitamin C-rich vegetables such as peppers and broccoli.