Lifestyle, health and disease prevention: the underlying mechanisms.

International studies in geographic pathology provide background information that a disease may have a quite different incidence and resulting mortality as a function of area of residence. Investigations in animals can model fairly precisely what is learned through such international research, and provide the basis for examining relevant hypotheses and, more importantly, possible mechanisms of action. These approaches can yield public health recommendations and health promotion activities. Regular intake of foods rich in saturated fats, such as meat and certain dairy products, raises the risk of coronary heart disease, especially in smokers. The total mixed fat intake is associated with a higher incidence of the nutritionally linked cancers (i.e. of the postmenopausal breast, distal colon, prostate, pancreas, ovary and endometrium). Monounsaturated oils, such as olive or canola oil, are low-risk fats, as shown in animal models, and through the finding that the incidence of coronary heart and neoplastic diseases is lower in the Mediterranean region, where such oils are customarily used. Fish and fish oils are protective. The associated genotoxic carcinogens for several of these cancers, and also in heart disease causation, are heterocyclic amines, produced during the broiling and frying of creatinine-containing foods such as meats. Excessive salt intake is associated with high blood pressure and with stomach cancer, especially with inadequate intake of potassium, from fruits and vegetables, and calcium from certain vegetables and low-fat dairy products. Bran cereal fiber intake, especially with adequate calcium, yields an increased stool bulk, eliminating factors involved in colon and breast cancer. Vegetables and fruits, as well as soy products, are rich in antioxidants that are essential to lower disease risk stemming from reactive oxygen species in the body. Green and black tea are excellent sources of such beneficial antioxidants of a polyphenol nature, as are cocoa and chocolates. Antioxidants also extend healthy aging and may protect against Alzheimer's and Parkinson's diseases. Nutritional lifestyles can be described for most populations in the world and offer the possibility of a healthy long life.