Diet and the prevention of cancer.

Cancer ranks as the second-leading cause of death in developed countries and diet has long been suspected as playing a prominent role in its etiology. As a result, a substantial amount of research has been devoted to this field of study. Given the epidemiologic and biologic credibility, it is reasonable to attempt to identify specific nutrients, foods, or combination of these that are causally related to the development of cancer. Various study designs have been employed to generate and test specific hypotheses. In this review, we approach the dietary prevention of cancer primarily from an epidemiologic perspective. We examine the growing body of evidence on dietary etiologic factors and explore the practical prospects for prevention of cancer overall. An attempt is also made to explain inconsistencies in the findings and provide ideas for future research efforts in this field.