Single-nutrient effects on immunologic functions. Report of a workshop sponsored by the Department of Food and Nutrition and its nutrition advisory group of the American Medical Association.

Immune system dysfunction can result from singlie-nutrient deficiencies or excesses, alone or in combination with generalized protein-energy malnutriton. Acquired immune dysfunctions in man occur with deficiencies of iron, zinc, vitamins A and B12, pyridoxine, and folic acid and with excesses of essential fatty acids and vitamin E. Additional micronutrients are important for maintaining immunologic competence in animals. Deficits or excesses of many trace elements and single nutrients thus have potential for causing immune dysfunctions in man. Since nutritionally induced immune dysfunction is generally reversible, it is important to recognize and identify clinical illnesses in which immunologic dysfunctions are of nutritional origin. Correction of malnutrition should lead to prompt reversal of acquired immune dysfunctions.