Diet and cancer.

Since unbalanced diets may increase the carcinogenic risk for certain organs, a balanced form of nutrition is to be recommended from the present point of view. It can also be recommended to avoid hyperalimentation, since this seems to have a positive effect on the cancer mortality risk; furthermore, ideal-weight individuals run a definitely lower risk of suffering a cardiac infarct than overweight individuals. Certain anticancer diets cannot be established. But the intake of juices and salads with a high vitamin C content can inhibit the formation of nitrosamines directly after the intake of food, because the nitrosation is prevented by nitrite interception. Negative influences of diets with a high fiber content are not known. Positive effects are discussed. Since it also prevents obstipation, it can well be recommended. Since dietary habits cannot shortly and easily be changed and changes in nutrition have a considerable impact on the personal quality of living, recommendations favoring certain diets should be given with all due caution. In our opinion the scientific basis for recommendations seems to be too small to justify very restrictive diets for cancer prevention.