Men interested in lowering their risk of prostate and other cancers should consider eating at least five servings of tomato-based products a week, according to scientific research being presented at the fourth annual World Congress on the Processing Tomato on Saturday, June 10 in Sacramento. A number of studies have already cited lycopene, a naturally occurring substance in tomatoes, as one of the substances that may be associated with the reduced risk of prostate and other cancers.