During recent years the concept of deficiency disease has been enlarged. It is becoming increasingly apparent that chronic vitamin deficiency produces a variety of vague borderline states of ill health that have no place in existing nomenclature. These conditions, however, seldom appear uncomplicated or well defined. The contributory factors are more complex than those operative in the laboratory, where the environment of the experimental animal is subject to strict control. It is probable, therefore, that the resulting clinical picture in man is not the simple expression of lack of a single factor as a vitamin. Deficient supply of other essential food substances such as protein, iron, calcium, phosphorus and iodine undoubtedly contribute to the syndrome. We have encountered indications of deficiency disease in forty-seven cases of chronic ulcerative colitis. These observations have been drawn from seventy-five consecutive cases seen in hospital, dispensary and private practice in New York City. They