Influence of diet, vitamins and chemotherapeutic agents on gastrointestinal cancer.

Dietary influences play a major role in the pathogenesis of most gastrointestinal malignancies. However, it has been difficult to define which dietary components will be most significant for any given individual. In this article we discuss the methodological challenges to research in this field as well as recent observations that have been made on the role of dietary factors in specific digestive tract neoplasms.