This handbook shows that approximately one in ten cancers in western populations is due to an insufficient intake of fruit and vegetables, a finding that should encourage all organizations as well as governments to continue efforts to increase or maintain fruit and vegetable intake as an important objective of programs to improve nutrition to reduce the burden of cancer and other chronic diseases. The clearest evidence of a cancer-protective effect of eating more fruits is for stomach and esophageal cancers. Similarly, a higher intake of vegetables probably reduces the incidence of cancer of esophagus and colon-rectum. Fruit and vegetables contain many nutrients; they also contain other bioactive compounds that may influence many aspects of human biology and related disease processes.