Worldwide prevention of cancer and other chronic diseases based on knowledge of mechanisms.

International research, particularly as part of US/Japan programs, has led to major advances in knowledge of causes of heart disease, stroke, many types of cancer and diabetes, showing that individual lifestyle is associated with these diseases. In Japan, a major health problem is high blood pressure and stroke, and cancer of the stomach, from excessive use of salt and salted, pickled foods, and the relative low intake of protective fruits and vegetables. We identified a likely gastric carcinogen, 2-chloro-4-methylthiobutanoate, in salted, pickled fish. In the Western world, heart disease and cancer of the breast, colon, rectum, prostate, pancreas, ovary and endometrium relate to a nutritional tradition too high in total fat and fried or broiled meats, and too low in fiber, vegetables and fruits. The cooked meats contain genotoxic chemicals, heterocyclic amines, causative elements in heart disease and the nutritionally linked cancers. Decreasing total fat intake, from 40 to 20% of calories and a greater use of starches such as rice, pasta, potatoes and whole grain bread, as well as daily intake of five to nine vegetables and fruits would be beneficial. Adults should consume 2.5 l of fluids per day. Green or black tea and fruit juices have health promoting properties. Regular exercise contributes to good health, and to the avoidance of obesity, a major problem in the USA and of increasing importance in Japan. Avoidance of a risky lifestyle would likely prevent diseases important not only for the individual and his family, but with major impact in lowering medical care costs. Tobacco and cigarette use, particularly on a Western diet, involve a high risk of heart attacks, and cancers of the lung, pancreas, kidney, urinary bladder, and cervix, accounting for 35% of medical care expenditures.