300. Early History Of Pellagra

Pellagra is a disease of man which is confined to relatively few places. It was discovered in Northern Spain by Casal in 1735 (1), but for many years it was most common in parts of Italy. Aside from Italy and Spain, pellagra has been prevalent during the last century in parts of France, the Balkans, especially Roumania, and for a lesser time in Egypt. It has, still more recently, afflicted many people in the United States. In this country the disease was not recognized with certainty until 1908, but from that year its incidence rapidly increased until by 1917 there were recorded 170,000 cases of pellagra, principally located in the southern states.

301. Pellagra Symptoms

Pellagra is a disease involving the nervous system, the digestive tract and the skin. Usually one of the first symptoms is soreness and inflammation of the mouth followed by the appearance of remarkably symmetrical erythema on parts of the body. The nervous symptoms are more or less pronounced, and become gradually worse as the disease progresses. The spinal cord is especially the seat of injury, but the central nervous system is also involved in many instances.

302. Theories As To Its Cause

Several views have been proposed to explain the etiology of this disease. Marzari, more than a century ago expressed the belief that pellagra resulted from the excessive use of maize as food. Italian investigators later accepted the view that it was caused by eating mouldy maize, the symptoms being caused by a toxic substance produced during the spoilage of the grain. Two other theories have been advanced to account for its etiology: one that it is caused by an infecting organism, and the other that it is in some way related to faulty diet. None of these views have been established by entirely satisfactory evidence, but the data now point incon-trovertibly to a relation between the diet and pellagra. One group of investigators believes that pellagra is an infectious disease, but admits that lowered vitality from faulty nutrition is a very important predisposing factor. Another group holds that the syndrome results from the lack in the diet of a specific protective substance, and that it is, therefore, analogous to beri-beri and scurvy. Since almost all students of this disease are now agreed that there is some relation between the character of the diet and susceptibility to it, the present chapter will be limited to a discussion of the evidence of the role of nutrition as an etiological factor in pellagra. Roussel (2) as early as 1845 stated that the most effective treatment of pellagra is a milk diet. Lussana and Frua (3) in 1856 studied the effect of improvement of the diet of pellagrins, and reported that they reduced the mortality in about 8,000 cases, from 24.5 to 4.5 per cent, and that they increased the rate of recovery from 20 to 70 per cent. The idea that the disease could be prevented or cured by proper diet dates back many years.

In 1909 the American investigators Wussow and Grindley (4) emphasized the fact that the diet of the insane patients under their observation was mostly composed of vegetable products, and that it had an especially low content in animal protein. In the light of what has been said in earlier chapters about the specific dietary properties of the different kinds of vegetable and animal food-stuffs, which can be, to a truly remarkable extent, correlated with their biological function, we are able to appreciate the fact that a fairly satisfactory diet can be prepared from vegetable foods supplemented with small amounts of products of animal origin provided the selection of the articles which enter into the diet be a fortunate one. At the time of the investigations referred to, however, the significance of the proper selection of food for the promotion of well-being was not at all appreciated.