Nutrition: prospects for the 1990s.

For many decades there has been adequate information for the elimination of acute dietary deficiency diseases. Scurvy, beri-beri, and pellagra, once serious scourges, are now seen only rarely. The severe forms of protein-energy malnutrition, kwashiorkor and marasmus, have also decreased greatly. Nonetheless, mild to moderate forms of protein-energy deficiency, exacerbated by infection, continue to impair growth and development in a majority of the low-income pre-school age populations of most developing countries. Deficiencies of iron, iodine, and vitamin A are still widespread in developing countries. Fortunately, the success of the WHO/UNICEF "Child Survival and Development Revolution" in persuading most developing countries to introduce expanded programs of immunization, growth monitoring, and appropriate feeding of young children, control of diarrheal disease, and specific campaigns against avitaminosis A, iodine deficiency disorders, and the functional consequences of iron deficiency, will accelerate the decline of acute deficiency diseases in the developing world. Diets are changing among the more affluent in these countries, however, and it is time for them to stress dietary goals for the health of rich and poor alike. For the first time there is enough information regarding dietary risk factors for chronic disease to provide an opportunity in the 1990s to accelerate the dietary changes that have already brought significant health benefits to some populations in North America and Europe. The changes, which include a lower dietary intake of fat, particularly saturated fat, less salt, and more green and yellow vegetable and whole grain cereals, can be expected to influence favorably morbidity from cardiovascular diseases and some kinds of cancer. For maximum benefit, these measures need to be combined with the avoidance of obesity, reasonable physical activity, abstention from, or moderate use of, alcohol, and avoidance of tobacco in any form. Since there is already considerable momentum toward these changes in North America and some European countries, the 1990s are likely to see substantial further progress in the reduction of chronic diseases known to be influenced by diet.