[Nutrition and colorectal cancer]

Results from case-control studies and prospective studies suggest that diet is involved in the causation of large bowel cancer either as initiator, promoter, or inhibitor of carcinogenesis. There is fairly consistent evidence concerning the protective effect of green vegetables. There is some evidence relating fat intake or protein intake to colorectal cancer whereas fiber intake or calcium intake would be inversely related to colorectal cancer. Recent data suggest that tobacco could be involved in adenoma formation and alcohol in adenoma growth. Available data are not sufficient to serve as a basis for firm specific dietary advice. In the present situation it is attractive to investigate available hypotheses within the framework of intervention trials.