Fat Tolerance.—A determination of the fat tolerance is made coincidently with that of the protein. No additional fat is allowed until the protein tolerance reaches 1 gram per kilogram of body weight, unless the patient’s tolerance for protein is less than that. After which 25 grams of fat per day are added until there is no further loss of weight, taking care never to allow more than 40 calories per kilogram of body weight.
Reappearance of Sugar.—Should the urine again show the presence of sugar, another period of fasting lasting for twenty-four hours, or until the urine is again sugar free, must be instituted. After the second fast the increase in the diet may be twice as rapid as used after the first fast. However, it is not advisable to increase the amount of carbohydrates to more than half of that determined by the former tolerance for a period of two weeks, during which time the urine has been entirely sugar free, then the increase is made more slowly and the amount given should not exceed 5 grams a week.
Weekly Fast Days.—One day in seven should be set aside by the diabetic patient for fasting, when the carbohydrate tolerance is less than 20 grams. When, however, the tolerance is between 20 and 50 grams of carbohydrates, the patient may take one-half of his daily allowance of protein and fat and a certain amount of 5% vegetables as well upon the weekly fast day. When the tolerance reaches between 50 and 100 grams per day, vegetables of a higher carbohydrate content may also be included. If the carbohydrate tolerance should exceed 100 grams per day, the carbohydrates upon the fast day may be simply half of the amount allowed upon other days.
The Giving of Alkalies.—If acidosis is evident, as may be indicated by an excretion of diacetic acid, oxybutyric acid, or acetone in the urine, alkalies may be given. Bicarbonate of soda may be given in doses of 2 grams every 3 hours, as suggested by Hill and Eckman,[143] but this is not as a rule necessary, for, as Jacobi aptly remarks: “Prevention is the treatment of acidosis in children, and those susceptible to acidosis should not have fat.” What he has said for children holds good for adults. However, it is likewise true that fat must constitute a large part of a diabetic diet and the only way to prevent it poisoning, is to raise the fat in the diet gradually until the tolerance is determined.
Determining the Extent of Acidosis.—It will be remembered that in an earlier chapter it was found that the excretion of ammonia in the urine to a certain extent indicated the extent of the acidosis in the body, that is, if the ammonia output exceeds three or four grams a day (twenty-four hours), the extent of the acidosis is considerable, while if it falls below that amount it is not alarming. More exact methods, however, for the determining of the severity of the acidosis will be found in another part of this text, where the test for sugar and the acetone bodies will be explained in detail.
Dietetic Treatment.—The patient is placed upon a vegetable diet consisting of vegetables containing not more than five per cent. carbohydrate.[144] These vegetables have their carbohydrate content still further reduced by changing the water in which they are cooked three times. In many cases this will reduce their content as much as one-half.
A small amount of fat usually in the form of butter is allowed with these vegetables. The amount of 5% vegetables given must be carefully adjusted since the patient might readily take too much if allowed to follow the dictates of his appetite.
The carbohydrate intake during the first one or two days must be limited to 15 grams. This allows about 10 grams of protein, 7 grams of fat, and 15 grams of carbohydrates. Tea or coffee, without sugar or cream, may be given at each of the three meals.
The following table is included, showing the various foods arranged according to their carbohydrate content: