Tomato Products, Lycopene, and Prostate Cancer: A Review of the Epidemiological Literature

Abstract

In the past several years, 2 general lines of evidence have supported a role of lycopene in the prevention of certain malignancies, especially prostate cancer. First, important antioxidant properties of lycopene have been established (1). Given the relatively high concentrations of lycopene in the serum of many individuals and the potential role of oxidative stress in the formation or the progression of cancers, a potential anticancer influence of lycopene has been hypothesized. Second, a number of epidemiological studies have suggested that individuals with a relatively high intake of lycopene, particularly from tomato products, have a lower risk of prostate cancer (2). However, the association between tomato products or lycopene and lower prostate cancer risk, while suggestive, remains controversial, because not all the studies are supportive. The results from the epidemiological studies will be summarized here, and factors that may contribute to the apparent inconsistencies will be considered.