INTERMEDIATE METABOLISM OF THE FATS 407 



illustrate it in dogs. Suppose that suitable operation and overfeeding 

 have produced a condition where there is marked glycosuria on a kilo- 

 gram of lung, but sugar-freedom on 800 grams of lung, together with 

 a fair state of nutrition and entire absence of ketonuria. Now place 

 the dog on 600 to 800 grams of lung and 100 to 200 grams of suet, 

 according to the classical method. There is no glycosuria, weight is 

 gained, and the .condition is splendid for weeks and possibly months. 

 The treatment is highly successful. Closer examination shows the 

 presence of hyperglycemia and slight ketonuria 1 which are usual in 

 the patients of corresponding type. Glycosuria follows, illustrating 

 the spontaneous downward progress which the authorities describe. 

 This is cleared up by a few fast-days on the Naunyn plan, and the diet 

 is again adjusted; it may now be 400 grams of lung and 200 grams 

 of suet. The gain in weight continues as before, with hyperglycemia, 

 ketonuria and subsequent glycosuria. Again the fast days are used 

 and the protein diminished, so that the diet is perhaps 200 grams of 

 lung and 200 grams of suet. The same cycle is repeated. Now the 

 dog is in splendid condition and spirits, the coat sleek, the appearance 

 such that he might create a good impression out walking in the park, 

 only he has a difficulty in remaining sugar-free on even the protein 

 minimum, and the fat may be pushed higher to maintain nutrition 

 against the repeated fast days. If the dog has actually been kept fat, 

 a fasting period about this time may diminish the glycosuria or it may 

 remain high. The previously lively and hungry animal begins to show 

 a curious little mournfulness, and complete repugnance to food. A day 

 or two later, vomiting of clear mucus begins, and the dog drinks and 

 vomits water. The acetone-reaction is heavy; the ferric chloride may 

 be heavy or slight. The alkali-reserve of the blood falls low, and the 

 complete picture of patients who go into fatal acidosis on fasting is 

 reproduced." 



As Joslin has pointed out, patients with severe diabetes may struggle 

 on, contending against many complications, and surviving for years on 

 an "atrocious diet," but let a doctor intervene, eliminate carbohydrates 

 from the diet and replace them by an equicalorific allowance of fat, 

 and the patient promptly dies in diabetic coma. The treatment is 

 completely successful, no doubt, in the sense that glucose temporarily 

 disappears from the urine, but the patient nevertheless dies. 



Diabetes is, in fact, a multiple metabolic disorder of which the failure 

 to utilize glucose is merely one manifestation which only indirectly 

 induces the fatal outcome. The exclusion of carbohydrates from the 

 diet renders calorific equilibrium and the maintenance of tissue- and 

 body-weight impossible, unless fat be partaken of, not in usual, but 

 even in unusual quantities. The diabetic, however, has a genuine 

 inability to oxidize fats, and intermediate products, of which the lead- 

 ing examples are oxybutyric and aceto-acetic acids, are formed and 

 accumulate in dangerous and ultimately fatal amounts. 



1 "Acetone bodies" in the urine. 



