Carbohydrates in the form of starch furnish a bulky food; and while a certain amount of bulk is necessary, an excess causes gastric disorders. Sugar is oxidized and absorbed more readily than starch. The monosaccharids are ready for absorption, dextrose being the sugar found in the blood. Some sugar is absorbed through the walls of the stomach, and this holds true of no other foods except alcohol and a very small per cent of peptones (proteids).
Sugar (sucrose), on account of its cheapness and complete absorption when taken in combination and moderation, makes a desirable quick-fuel food. Milk sugar (lactose) is equal in nutritive value to cane sugar. Being less sweet to the taste and more slowly absorbed it is often used to advantage for infant feeding and sick-room cookery, where expense is not considered. The usual retail price of milk sugar is about thirty cents per pound. Milk sugar, under ordinary conditions, does not ferment and give rise to an excess of acids.
Sugars are more rapidly oxidized than starches. The former may be compared to the quick flash of heat from pine wood, the latter to the longer-continued heat from hard wood.
The starches furnish the necessary bulk to our foods and are also proteid sparers. Proteids give such an intense heat that but for the starches much of their energy would be wasted.
The waste products of carbohydrates are carbon dioxide (C02) and water (H20), which leave the body through the lungs, skin, and urine.
The fats and oils also furnish heat and energy, and constitute the adipose tissue of the body. Examples: Fats of meat, butter, cream, olive oil, etc. They are an expensive concentrated fuel food, yielding two and one-fourth times as much energy as an equal weight of carbohydrates. To those who do not consider expense in feeding, there is a strong tendency to increase the use of fats and oils and decrease the carbohydrates, while
