The chief advantage of the skim-milk over the unskimmed is simply that it is more easy of digestion. Many persons who cannot take unskimmed milk for any length of time without its deranging the digestion, or, as is commonly said, making them bilious, can take with impunity milk from which the cream is removed. Although Salomon48 claims to have shown that glycogen is produced in the liver of rabbits fed upon pure olive oil, it is at least probable that fat is among the last of the substances undergoing this conversion, and in ordinary cases of diabetes it is rather its indigestible nature which renders it prudent to remove from milk the greater proportion of fat by skimming it off.
48 Virchow's Archiv, Bd. 61, Heft 3, 1874, 18.
Still more easily assimilable is the peptonized milk, in which the casein is at least partially digested, and it should be employed where there is any difficulty in the way of using the ordinary milks. Either skimmed or unskimmed milk may be used for peptonizing, the latter peptonized being quite as easy of digestion as the former unpeptonized. I have found the extractum pancreatis of Fairchild Brothers & Foster most successful in the peptonizing of milk, and according to the following directions: Into a clean quart bottle put 5 grains of extractum pancreatis, 15 of bicarbonate of sodium, and a gill of cool water; shake, and add a pint of fresh cool milk. Place the bottle in a pitcher of hot water or set the bottle aside in a warm place, usually for three-quarters of an hour. When the milk has acquired a slightly bitter taste, it has been completely peptonized—that is, the casein has been completely converted into peptone. After the process is complete the milk must be immediately put on ice.
It is not always necessary to completely peptonize the milk, and if the bitter taste is unpleasant the process may be stopped short of this by putting the milk on ice, the degree of digestion depending upon the length of time the milk is kept warm.
While I am confident that the promptest and most effectual method of eliminating sugar from the urine is by a milk diet, it occasionally happens that a patient cannot or will not submit to so strict a regimen. In other instances, again, it is not necessary to resort to it, because a less restricted diet answers every purpose.
A suitable diabetic diet would also be obtained by eliminating from the bill of fare all saccharine and amylaceous and other sugar-producing substances. Such a diet is, strictly speaking, impossible. For, apart from the fact just mentioned that even fats, as well as albuminous substances to a degree, are capable of producing glycogen, the monotony of a pure meat diet soon becomes unbearable, to say nothing of other derangements it may produce. Fortunately, it is not necessary that such an exclusive diet should be maintained, for certain saccharine foods seem capable of resisting the conversion into sugar more than others. Sugar of milk, or lactin, has already been mentioned as one of these, and to it may be added the sugar of some fruits, and probably also inosit or muscle-sugar, mannite or sugar of manna, and inulin, a starchy principle abundant in Iceland moss. It is found also that there are many vegetable substances containing small quantities of sugar and sugar-producing principles which may be used with impunity in at least the milder forms of diabetes. This being the case, a bill of fare for diabetics may be constructed quite liberal enough to satisfy the palate of most reasonable persons by whom it is attainable.
FOOD AND DRINK ADMISSIBLE.—Shell-fish.—Oysters and clams, raw and cooked in any way, without the addition of flour.
Fish of all kinds, fresh or salted, including lobsters, crabs, sardines, and other fish in oil.
Meats of every variety except livers, including beef, mutton, chipped dried beef, tripe, ham, tongue, bacon, and sausages; also poultry and game of all kinds, with which, however, sweetened jellies and sauces should not be used.
Soup.—All made without flour, rice, vermicelli, or other starchy substances, or without the vegetables named below as inadmissible. Animal soups not thickened with flour, beef-tea, and broths.