The utilization of fat in diabetes. ∗

Abstract

It is a well attested fact that in severe diabetes there is a pronounced tendency for the fat of the blood to be abnormally high (using the term fat to include all compounds of the fatty acids). In certain instances the fatty compounds may increase beyond the ability of the blood to carry them in solution and there is produced a visible milkiness, while in extreme cases the fat may reach very high figures—twenty percent and over having been reported. In a discussion of diabetic lipemia some time ago 1 evidence was collected which indicated that the lipemia of diabetes was the result of a diminished outflow of fat from the blood, directly or indirectly connected with the pancreatic insufficiency. Direct proof of diminished ability of the diabetic organism to utilize fat was however lacking, and it was with desire to obtain positive evidence on this point that the following work was undertaken. Experiments to elucidate this point were planned and carried out by Allen 2 and Wishart some years ago, but owing to loss of the data during the war they were never recorded. The subject is one of great practical importance, for while insulin has provided a means of abolishing the acute symptoms and saving life it does not cure diabetes, and its continued administration especially in large doses is, to say the least, inconvenient. Recourse must still be had to diet, and since fat is one artcle of food that does not form carbohydrate—or does so least readily—the use of high fat diets in diabetes has had a considerable vogue (Newburgh and Marsh, Petren) notwithstanding the warning of Allen that while good results may be obtained temporarily there is great danger of disaster.

The experiments were planned so as to provide a direct comparison between the effects of fat on the blood lipoids in a normal animal and in the same animal rendered diabetic by removal of most of the pancreas. Normal young adult dogs were taken and their blood reaction to fat studied by a series of feedings with analysis of the blood lipoids by the micro methods. About ninetenths of the pancreas was then removed leaving the part around and near the main duct, and, after recovery, the fat feedings were repeated. The diet after the operation was high protein and low fat. Sugar appeared in the urine at once after the operation.