Vitamin E, selenium and soy won't prevent prostate cancer

Despite earlier promise, three nutrients - vitamin E, selenium and soy - do not seem to prevent prostate cancer in men with precancerous prostate lesions, Canadian researchers report.

The door is open regarding using these supplements to prevent prostate cancer before precancerous lesions have formed.

The results confirm the findings of the two recent prospective trials, which also found that vitamin E, vitamin C and selenium do not prevent prostate cancer. The results of these trials were published in the Jan. 7 issue of the Journal of the American Medical Association. Other recent studies have suggested that vitamins, B, C, D, E, folic acid and calcium taken alone, or in various combinations, aren't effective for cancer prevention.

"There is some evidence from laboratory and population studies that soy protein or its components might reduce risk of prostate cancer," said Eric Jacobs, strategic director for Pharmacoepidemiology at the American Cancer Society.

In this study, soy protein had no apparent effect on the development of prostate cancer among men who already had precursor lesions in the prostate, Jacobs noted. "However, it remains possible that soy could reduce risk of developing prostate cancer by inhibiting earlier stages of prostate cancer development, or that soy could reduce the risk of recurrence or disease spread in men with prostate cancer.