In considering the progress made by the medical profession in the treatment of diabetes mellitus up to the present time, two factors appear of major significance: (1) the discovery that the disease is definitely related to the pancreas and the islands of Langerhans within the pancreas, and (2) the fact that the disease may be controlled through proper adjustment of the diet. Of these two factors, until the recent discovery by Banting, the dietetic control has been the more important. Even with the use of "insulin," however, diet adjustment is a matter of major consideration. As pointed out by Newburgh and Marsh,1 it was customary at first to use a liberal protein fat diet in the treatment of diabetes mellitus. In 1914, Allen introduced the principle of undernutrition with the object of relieving the strain on the pancreas and of stopping the progress of the disease. Following the leadership of