"Current evidence suggests that exercise may be a crucial weapon in reducing the risk of some cancers," the report claimed. "Studies show that active people are less likely to develop colon cancer than sedentary individuals, and that women who exercise can reduce their breast cancer risk."
When it comes to reducing the risk of heart disease, regular exercise is associated with a sharp reduction in heart attacks and cardiac deaths.
While studies continue on whether vitamin E and selenium can help reduce prostate cancer risk, data already show that beta carotene actually boosts the risk of lung cancer in smokers, Health Watch says.
And zinc, as well as high doses of folic acid, may also do more harm than good for men seeking to ward off prostate cancer.
Health Watch says vitamins are not recommended for heart disease prevention. Trials of B vitamins have failed to demonstrate protection against heart disease. But people who eat fish twice a week enjoy a reduced risk of heart attack and sudden cardiac death.
