This section is from the book "Meals Medicinal", by W. T. Fernie. Also available from Amazon: Meals Medicinal: With "Herbal Simples" Curative Foods From the Cook in Place of Drugs From the Chemist.
There are several sorts of Sugar, all belonging chemically to carbohydrate constituents of food, and which include Cane Sugar, Grape Sugar (or Starch Sugar, which is glucose), Sugar of Milk (or lactose), and a Sugar found in the juice of asparagus (as well as in some of the muscular bodily tissues), which is "inosite." Fruit Sugar (fructose) is discovered, together with some Grape Sugar, in almost all sweet fruits. The same can be made chemically from Cane Sugar when fermented, or if boiled with acids, and the Cane Sugar is then said to be "inverted".
This Fruit Sugar is more slow to ferment (with yeast) than is Cane Sugar; it is also called "Icevulose," because having a left-hand rotary relation to polarized light under the microscope. On the contrary, Grape Sugar is "dextrose," because having a right-hand rotary direction under similar conditions; such Sugar being found especially in grapes. Fruit Sugar (Iaevulose) forms a thick syrup, which will dry under heat to a gummy, deliquescent mass. It is prepared in both powder, and a honeyed form, this latter being known as "Satrap" Iaevulose. If the same becomes firm by a cold temperature, its consistence like honey may be restored by placing its vessel in warm water. Then as such it can be spread on bread, and taken with tea, or coffee. Professor Worm-Muller, even after allowing large quantities of Iaevulose to diabetic patients, could find no trace of it in their urine. This kind of sugar, as fattening and highly nutrient, is further indicated for pulmonary consumption. It is, moreover, an excellent medium for promoting strength in the weakly and convalescent; also for giving physical energy to young persons of athletic pursuits.
A Iaevulose Chocolate is made for the last-named purpose.
The uses of Sugar generally for medicinal purposes are of modern date; they have been proved in two directions. Sugar has considerable influence on the separation of the gastric juices: Dextrose (Grape Sugar) reduces the secretion of the gastric juice to one-tenth part within the first three hours, and binds the acids; Fruit Sugar (Iaevulose), on the other hand, reduces the gastric juice only to one-half, and correspondingly affects the acids in only a minor degree. From the different actions of these two Sugars it becomes clear that in certain forms of disease of the stomach, in which it is important to reduce the acidity, as in ulcers of the stomach, then Grape Sugar (dextrose) is of great remedial value; while, on the other hand, in normal digestive conditions, or even in states when the gastric juices are insufficiently generated, and produced, the partaking of such Sugar should be very moderate, or digestion will be retarded. It has been also proved that by too free a use of Cane Sugar the digestive fluids are clogged, and find a difficulty in reaching the intestines.
For these reasons Fruit Sugar is of more value when saccharine carbohydrates are needed for maintaining the bodily energies, and for building up the bodily structures; and inasmuch as it would seldom be possible to consume the quantity of fruit needed to supply the requisite quantity of Fruit Sugar for a cure, it may be taken as "Iaevulose," to be had from the manufacturing chemist (Schering"s Factory). Fruit jams may be made therewith instead of with Cane Sugar; which faculty would be quite an acquisition for persons with weak digestive powers, and faulty gastric juices. The laevulose is a non-perishable syrup, freely soluble in hot water. Mothers may wisely give it made as a sweetmeat to their children instead of acid drops, and other lollipops.
In A Vindication of Sugar, dedicated to the Ladies (1715), "Nature," says the writer, "who has given you Ladies more accurate, and refined palates, has made you more competent judges of taste, as not being debauch'd by soure, and uncouth wines, or drams, or offensive smoak, or the more sordid juice of the Indian henbane, (which is tobacco,) or vitiated by salt, or soure pickles, - too much the delight of our coarser sex! For these reasons the great Evelyn chose a young damsel of virgin unprejudic'd palate to judge of his curious, and fav'rite liquor, Cyder." Being, moreover, of a pleasant wit, he further allows that "the fair sex who love their beauty, or are of fine proportions, must be a trifle cautious about Sugar, which may dispose them to be fatter than they may desire to become, who are afraid for their fine shapes; yet for this there is a compensation, as it gives them a very wholesome, and goodly countenance, and sweetens peevish, and cross humours." Dr. Weber has found that, with a proper diet, by the use of Fruit Sugar even patients suffering from pulmonary consumption, with extensive lung mischief, have recovered.
By such means the presence of carbonic acid in the blood is increased, and the bacilli of tubercular disease perish because meeting with this excess of carbonic acid over the oxygen necessary for their maintenance. Other Sugars will aid in a like method of cure, such as Malt Sugar, and Sugar mixed with diastase (the ferment of malt). Grape Sugar, and the carbohydrates related to it, are highly injurious to diabetic patients, because the oxidation of Sugar is with these sufferers deficient in the system, and thereby they become extraordinarily susceptible to tubercular disease; but the Fruit Sugar possesses directly opposite physiological properties, though closely related in chemical constituents. As much fruit as possible is to be advised for diabetic patients, but in an easily digestible form as to the vegetable cellulose, (by boiling). Carbohydrates (which possess twice as much hydrogen as oxygen) comprise fructose, Fruit Sugar (laevulose), Cane Sugar (glucose), starch (soluble, as dextrin), and cellulose. Early oranges contain only from 2 to 3 per cent of carbohydrates altogether, of which Fruit Sugar (laevulose) is the chief; and even sweet oranges have not more than from 5 to 7 per cent of the same, so that in most cases they may be allowed.