Nutrition has been recognized as a major determinant of health for centuries. Tradi tionally, nutritional sciences have primarily targeted the prevention of diseases resulting from clinical deficiencies of essential nutrients, such as scurvy and rickets. Contempo rary nutritional research has focused on the prevention of major diseases of Western civilization, particularly cardiovascular disease and cancer, as well as promoting mater nal and child health and healthy aging. Heart disease and cancer, which were rare in most developing countries several decades ago, are increasing dramatically in these countries, in parallel with economic development and dietary transitions, decreases in infectious diseases, and increasing sedentary lifestyle and obesity. Substantial evidence indicates major chronic diseases such as coronary heart disease, type 2 diabetes, and some cancers are largely preventable by relatively simple diet and lifestyle modifications. Despite the great potential of nutrition in preventing diseases and improving health, nutrition is not routinely emphasized in the education and training of physicians and other health care professionals. This has resulted in inadequate nutritional knowledge and lack of skills in providing dietary counseling among many health care professionals. Further more, in the past decade, the public''s access to nutritional information has been increas ing rapidly, particularly through the Internet. There are now hundreds of websites providing a wide range of nutritional information and selling numerous dietary products. Because of the explosion in nutritional information, the public''s demand for nutritional advice has been increasing rapidly and will continue to rise.
