• Between 25% and 50% of patients admitted to an acute medical service are malnourished. Physicians are often unaware which patients are admitted at nutritional risk and make no attempt to arrest further nutritional decline until a dramatic deterioration has occurred. We studied all patients admitted to an acute medical ward service before and after their physicians were taught to recognize nutritional deficiency early and to intervene appropriately. During the initial period, the house staff correctly identified two (12.5%) of 16 patients as being malnourished. During the posteducation period, physicians correctly Identified all 14 patients admitted at nutritional risk (100%), using a simple screening device that required only routine admission data. In all cases, the appropriate nutritional Intervention was subsequently made. Results were further validated using a pretest and posttest, showing a significant Improvement in nutritional knowledge. We conclude that physicians are not presently being taught to recognize malnutrition, that such malnutrition is iatrogenically worsened in the hospital, and that physician education can effectively correct this problem. ( Arch Intern Med 1987;147:1462-1465)