Prospective studies suggest that people with high intakes of fruit and vegetables or blood antioxidant concentrations 1 2 in the highest quantile of the distribution have low risks of epithelial cancers, 3 coronary heart disease, 4 and stroke. 5 The anticarcinogenic properties of antioxidants in animal and cell culture systems and their ability to reduce oxidation of low density lipoproteins provide plausible biological explanations for the epidemiological associations. 67