Diet and cancer prevention: the fiber first diet

Diet can play a major role in cancer prevention. The internationaldifferences in cancer incidence are largely accounted for by lifestylepractices that include nutrition, exercise, and alcohol and tobacco use.About 50% of cancer incidence and 35% of cancer mortality in the U.S.,represented by cancers of the breast, prostate, pancreas, ovary,endometrium, and colon, are associated with Western dietary habits. Cancerof the stomach, currently a major disease in the Far East, relates todistinct, specific nutritional elements such as excessive salt intake. Forthese cancers, information is available on possible initiating genotoxicfactors, promoting elements, and prophylactic agents. In general, thetypical diet in the United States contains low levels of the potentcarcinogenic agents, heterocyclic amines, formed during the cooking ofmeats. It provides only about half the potent appropriate fiber intake andis high in calories. About twice as many calories as would be desirablecome from fat, certain kinds of which enhance the development of cancers.Other foods with functional properties, such as soy products and tea, canbe beneficial. To achieve reduction in risk of certain cancers, diet mustbe optimized, primarily to reduce caloric intake and the fat component. Thelatter should be 20% or less of total caloric intake and fiber should beincreased to 25- 35 g per day for adults. One approach to achieving thesegoals is the Fiber First Diet, a diet designed around adequate fiber intakefrom grains, especially cereals, vegetables, legumes, and fruits, whichthereby reduces both calorie and fat intake. Such dietary improvements willnot only reduce cancer and other chronic disease risks, but will contributeto a healthy life to an advanced age. A corollary benefit is a lower costof medical care.