Fig. 53.

Fig. 53.

The proper digestion of food depends on the wants of the body, and on its power of appropriating the aliment supplied. The best of food can not be properly digested when it is not needed. All that the system requires will be used, and the rest will be thrown out by the several excreting organs, which thus are frequently overtaxed, and vital forces are wasted. Even food of poor quality may digest well if the demands of the system are urgent. The way to increase digestive power is to increase the demand for food by pure air and exercise of the muscles, quickening the blood, and arousing the whole system to a more rapid and vigorous rate of life.

We are now ready to consider intelligently the following general principles in regard to the proper selection of food:

Vegetable and animal food are equally healthful if apportioned to the given circumstances.

In cold weather, carbonaceous food, such as butter, fats, sugar, molasses, etc., can be used more safely than in warm weather. And they can be used more safely by those who exercise in the open air than by those of confined and sedentary habits.

Students who need food with little carbon, and - women who live in the house, should always seek coarse bread, fruits, and lean meats, and avoid butter, oils, sugar, and molasses, and articles containing them.

Many students and women using little exercise in the open air grow thin and weak, because the vital powers are exhausted in throwing off excess of. food, especially of the carbonaceous. The liver is especially taxed in such cases, being unable to remove all the excess of carbonaceous matter from the blood, and thus "biliousness" ensues, particularly on the approach of warm weather, when the air brings less oxygen than in cold.

It is found, by experiment, that the supply of gastric juice, furnished from the blood by the arteries of the stomach, is proportioned, not to the amount of food put into the stomach, but to the wants of the body; so that it is possible to put much more into the stomach than can be digested. To guide and regulate in this matter, the sensation called hunger is provided. In a healthy state of the body, as soon as the blood has lost its nutritive supplies, the craving of hunger is felt, and then, if the food is suitable, and is taken in the proper manner, this sensation ceases as soon as the stomach has received enough to supply the wants of the system. But our benevolent Creator, in this as in our other duties, has connected enjoyment with the operation needful to sustain our bodies. In addition to the allaying of hunger, the gratification of the palate is secured by the immense variety of food, some articles of which are far more agreeable than others.

This arrangement of Providence, designed for our happi-ness, has become, either through ignorance' or want of self-control, the chief cause of the many diseases and sufferings which afflict those classes who have the means of seeking: a variety to gratify the palate. If mankind had only one article of food, and only water to drink, though they would have less enjoyment in eating, they would never be tempted to put any more into the stomach than the calls of hunger require. But the customs of society, which present an incessant change, and a great variety of food, with those various condiments which stimulate appetite, lead almost every person very frequently to eat merely to gratify the palate, after the stomach has been abundantly supplied, so that hunger has ceased.

When too great a supply of food is put into the stomach, the gastric juice dissolves only that portion which the wants of the system demand. Most of the remainder is ejected in an unprepared state; the absorbents take portions of it into the system; and all the various functions of the body, which depend on the ministries of the blood, are thus gradually and imperceptibly injured. Very often, intemperance in eating produces immediate results, such as colic, headaches, pains of indigestion, and vertigo.

But the more general result is a gradual undermining of all parts of the human frame; thus imperceptibly shortening life, by so weakening the constitution that it is ready to yield, at every point, to any uncommon risk or exposure. Thousands and thousands are passing out of the world, from diseases occasioned by exposures which a healthy constitution could meet without any danger. It is owing to these considerations that it becomes the duty of every woman who has the responsibility of providing food for a family to avoid a variety of tempting dishes. It is a much safer guide to have only one kind of healthy food for each meal, rather than the too abundant variety which is often met at the tables of almost all classes in this country. When there is to be any variety of dishes, they ought not to be successive, but so arranged as to give the opportunity of selection, How often is it the case that persons, by the appearance of a favorite article, are tempted to eat merely to gratify the palate, when the stomach is already adequately supplied. All such intemperance wears on the constitution, and shortens life. It not unfrequently happens that excess in eating produces a morbid appetite, which must constantly be denied.

But the organization of the digestive organs demands not only that food should be taken in proper quantities, but that it be taken at proper times.

Fig. 54 shows one important feature of the digestive organs relating to this point. The part marked L M shows the muscles of the inner coat of the stomach, which run in one direction, and C M shows the muscles of the outer coat, running in another direction.

As soon as the food enters the stomach, the muscles are excited by the nerves, and the peristaltic motion commences: this is a powerful and constant exercise of the muscles of the stomach, which continues until the process of digestion is complete. During this time the blood is withdrawn from other parts of the system, to supply the demands of the stomach, which is laboring hard with all its muscles. When this motion ceases, and the digested food has gradually passed out, nature requires that the stomach should have a period of repose. And if another meal be eaten immediately after one is digested, the stomach is set to work again before it has had time to rest, and before a sufficient supply of gastric juice is provided.