From the standpoint of prevention, the researches in this field have, however, been of the greatest importance. It is abundantly established that pellagra is in some manner caused by faulty diet, and that the type of diet which is concerned in its etiology is one derived largely from milled cereals, tubers, molasses, syrup and fat pork (23). It is absolutely proven in numerous cases, that milk is the most effective therapeutic agent, and that the inclusion of a liberal amount of milk, together with meats, eggs and leafy vegetables in the diet will prevent the disease. All authorities are agreed that there is but one effective method of prevention or of treatment for pellagra, viz., a satisfactorily constituted diet.

Pellagra afflicts the people of the South, largely because they are engaged in the cultivation of a cash crop (cotton), or in its manufacture. Under such conditions the food supply is derived in great measure throughout the year from the grocery store, and during the winter season, practically exclusively so.

The grocer, in modern civilized and progressive communities, has come in recent times, to restrict his line of foods in great measure to milled cereals and canned goods which are derived either from muscle meats or from seed products (beans, peas, corn, etc) and molasses. As has been repeatedly shown by experiments on animals, it is not possible to prepare from such a list of foods a diet which will promote well-being over any prolonged period. On such a diet ill health and inefficiency are to be expected, and experience has abundantly shown that this result is being realized where such dietary practices prevail.

The knowledge of the methods by means of which pellagra can be eradicated is, therefore, quite adequate, and as soon as it can be applied practically where needed, the disease may confidently be expected to disappear in proportion to the extent to which reform in the diet of the population can be brought about. The reduction of the consumption of milled cereal products, molasses and fats, and a substitution of liberal amounts of the protective foods, milk and the leafy vegetables will free any community from this scourge, which is now (1921) reported to afflict more than two hundred thousand people in the United States.

Fig. 13. - This picture illustrates the emaciated appearance of a middle aged rat after being fed about four months on a diet consisting of bolted flour, degerminated corn meal, rice, sugar, starch, pork fat, molasses, sweet potato, and cabbage. Such a diet has been reported by Goldberger to have produced pellagra in man in five and a half months. This diet affords wide variety and consists of wholesome food products, yet fails to maintain normal nutrition because it contains too little of the protective foods, milk, eggs and the leafy vegetables.

Fig. 14. - Illustrates the remarkable bilateral symmetry of the skin lesions of pellagra. - Courtesy of the Thompson Pellagra Commission.

Fig. 15. - Illustrates the skin lesions on the arm and hand of a pellagrin. - Courtesy of the Thompson Pellagra Commission.