SummaryThe epidemiologic data tend to support an association between intake of tomato-based foods and a lower risk of prostate cancer. The observed inverse association may be due to lycopene though this is unproven at this point. Even two servings a week of a rich source of bioavailable lycopene, such as tomato sauce, was related to a substantially lower risk of prostate cancer. Whereas chance alone is highly unlikely to account for the consistent inverse association with tomato-based products, confounding by other variables, particularly dietary, cannot be definitively excluded as alternative explanations. Of greatest concern is that a lycopene-rich diet is acting as an indicator of a diet rich in vegetables and fruits that may lower risk of prostate cancer through other phytochemicals. An important historical lesson is provided by β-carotene, for which an abundance of evidence based on questionnaires and blood levels suggested a benefit on various cancers (93), particularly lung cancer, but recent inter...