Dietary factors in colon carcinogenesis with special emphasis on the role of dietary fat and dietary fibre.

Abstract:  Dietary factors other than fat and fibre have been reported to influence colon cancer risk, in particular a protective effect of cruciferous vegetables (Graham et al., 1978) and an increased risk associated with beer consumption (Breslow and Enstrom, 1974) have been suggested. The role of these dietary aspects is however less well understood than that of fat and fibre; for beer consumption the statistical association has been suggested to be a non-causal nature (Jensen, 1979; Jensen, 1982). In summary then the epidemiological pattern of colon cancer points to various aspects of diet as a determinant of colon cancer risk. If - as suggested - an imbalance between the intake of fat and fibre is of importance mediated by the fecal concentration of bile acids further studies should attempt to clarify the relative role of these two items in addition to shedding further light on the role of other dietary aspects, for which our present knowledge is even more incomplete. With a view to cancer prevention it may prove more productive to give priority to a search for items that have a protective effect. It may thus be more acceptable to high risk populations to add perhaps only a limited amount of "roughage" to their diets than to reduce the daily fat-intake.