Medical literature is plethoric with discussions of various theories on the etiology of peptic ulcer, though very little has been proved that will account for the increase in the incidence of the disease. The work of Rosenow and a number of other observers seems to make it certain that an exciting cause, and a probable factor in all cases, is infection, not with a specific bacterium but with a number of pathogenic organisms. The problem of lowered resistance or of the conditions in the stomach or duodenum that predispose to infection, resulting in ulcer, is yet to be solved. However, some of the facts brought out in recent studies on nutrition, particularly with reference to diets deficient in vitamins, if applied to the eating habits of the American people may suggest methods of preventing and curing gastric and duodenal ulcers. About ten years ago, McCollum, Simons and Parsons expressed the