[11] The system is gradually developed, and all changes of food, apparel, labor, exercise, or position, should be gradual. Even a change from a bad to a good habit, on this principle, should be gradual.

302. _Some temperaments require more stimulating food than others._ As a general rule, those persons whose sensations are comparatively obtuse, and movements slow, will be benefited by animal food; while those individuals whose const.i.tutions are highly impressible, and whose movements are quick and hurried, require a nutritious and unstimulating vegetable diet.

300. What kinds of food are appropriate to old age? Why? What kinds to childhood? Why? 301. What is the effect when there is a sudden change from a vegetable to an animal diet? How should all changes of the system be made? 302. Do different temperaments require different kinds of food? What general rule is given?

CHAPTER XVI.

HYGIENE OF THE DIGESTIVE ORGANS, CONTINUED.

303. The MANNER in which food should be taken is of much practical importance; upon it the health of the digestive organs measurably depends. But few circ.u.mstances modify the proper manner of taking food, or should exercise any controlling influence.

304. _Food should be taken at regular periods._ The interval between meals should be regulated by the character of the food, the age, health, exercise, and habits of the individual. The digestive process is more energetic and rapid in the young, active, and vigorous, than in the aged, indolent, and feeble; consequently, food should be taken more frequently by the former than by the latter cla.s.s.

305. In some young and vigorous persons, food may be digested in one hour; in other persons, it may require four hours or more. The average time, however, to digest an ordinary meal, will be from two to four hours. In all instances, the stomach will require from one to three hours to recruit its exhausted powers after the labor of digesting a meal before it will again enter upon the vigorous performance of its duties.

306. _Food should not be taken too frequently._ If food is taken before the stomach has regained its tone and energy by repose, the secretion of the gastric juice, and the contraction of the muscular fibres, will be imperfect. Again, if food is taken before the digestion of the preceding meal has been completed, the effects will be still worse, because the food partially digested becomes mixed with that last taken. Therefore the interval between each meal should be long enough for the whole quant.i.ty to be digested, and the time of repose should be sufficient to recruit the exhausted organs. The feebler the person and the more debilitated the stomach, the more important to observe the above directions.

303. Why is it important that we regard the manner of taking our food?

304. How should the intervals between meals be regulated? 305. What is the average time required to digest an ordinary meal? 306. Why should not food be taken too frequently?

_Observation._ In the feeding of infants, as well as in supplying food to older children, the preceding suggestions should always be regarded. The person who has been confined by an exhausting sickness, should most scrupulously regard this rule, if he wishes to regain his strength and flesh with rapidity. As the rapidity of the digestive process is less in students and individuals who are engaged in sedentary employments, than in stirring agriculturists, the former cla.s.s are more liable to take food too frequently than the latter, while its observance is of greater importance to the sedentary artisan than to the lively lad and active farmer.

307. _Food should be well masticated._ All solid aliments should be reduced to a state of comparative fineness, by the teeth, before it is swallowed; the gastric fluid of the stomach will then blend with it more readily, and act more vigorously in reducing it to chyme. The practice of swallowing solid food, slightly masticated, or "bolting"

it down, tends to derange the digestive process and impair the nutrition of the system.

308. _Mastication should be moderate, not rapid._ In masticating food, the salivary glands are excited to action, and some time must elapse before they can, secrete saliva in sufficient quant.i.ties to moisten it. If the aliment is not supplied with saliva, digestion is r.e.t.a.r.ded; besides, in rapid eating, more food is generally consumed than the system demands, or can be easily digested. Laborers, as well as men of leisure, should have ample time for taking their meals. Imperfect mastication is a prevailing cause of indigestion.

What persons would be benefited by observing the preceding remarks?

307. Why should food be well masticated? What is the effect of "bolting down" food? 308. How should mastication be performed? Why?

309. _Food should be masticated and swallowed without drink._ As the salivary glands supply fluid to moisten the dry food, the use of tea, coffee, water, or any other fluid, is not demanded by nature's laws while taking a meal. One objection to "washing down" the food with drink is, the aliment is moistened, not with the saliva, but with the drink. This tends to induce disease, not only in the salivary organs, by leaving them in a state of comparative inactivity, but in the stomach, by the deficiency of the salivary stimulus. Another is, large quant.i.ties of fluids, used as drinks, give undue distention to the stomach, and lessen the energy of the gastric juice by its dilution, thus r.e.t.a.r.ding digestion. Again, drinks taken into the stomach must be removed by absorption before the digestion of other articles is commenced.

_Observation._ Were it customary not to place drinks on the table until the solid food is eaten, the evil arising from drinking too much at meals would be obviated. The horse is never known to leave his provender, nor the ox his blade of gra.s.s, to wash it down; but many persons, from habit rather than thirst, drink largely during meals.

310. The peculiar sensation in the mouth and fauces, called thirst, may not always arise from the demand for fluids to increase the _serum_ (water) of the blood, as in the desire for drink attendant on free perspiration, for then, pure water or some diluent drink is absolutely necessary; but it may be the result of fever, or local disease of the parts connected with the throat. In many instances, thirst may be allayed by chewing some hard substance, as a dry cracker. This excites a secretion from the salivary glands, which removes the disagreeable sensation. In thirst, attendant on a heated condition of the system, this practice affords relief, and is safe; while the practice of drinking large quant.i.ties of cold fluids, is unsafe, and should never be indulged.

Why should all persons have ample time for eating? 309. Why are drinks not necessary while masticating food? Give the objections to "washing down" food. What observation relative to drink? 310. Does the sensation of thirst always arise from a real want of the system?

311. _Food or drink should not be taken when very hot._ When food or drink is taken hot, the vessels of the mucous membrane of the gums, mouth, and stomach are unduly stimulated for a short time; and this is followed by reaction, attended by a loss of tone, and debility of these parts. This practice is a fruitful cause of spongy gums, decayed teeth, sore mouth, and indigestion.

312. _Food or drink should not be taken very cold._ If a considerable quant.i.ty of very cold food or liquid be taken immediately into the stomach, the health will be endangered, and the tone of the system will be impaired, from the sudden abstraction of heat from the coats of the stomach, and from surrounding organs, to impart warmth to the cold food or drink. This arrests the digestive process, and the food is retained in the stomach too long, and causes oppression and irritation. Consequently, food and drink that are moderately heated are best adapted to the natural condition of the digestive apparatus.

_Observation._ Food of an injurious quality, or taken in an improper manner, affects the inferior animals as well as man. The teeth of cows that are closely penned in cities, and are fed on distillery slops, or the unhealthy slops and remnants of kitchens, decay and fall out in about two years. Can the milk of such diseased animals be healthy--the proper nourishment for children?

Give instances when it does and when it does not. 311. Why should not food or drink be taken hot? 312. Why should they not be taken cold?

Show some of the effects of improper food upon the inferior animals.

313. The CONDITION of the system should be regarded when food is taken. This is necessary, as the present and ulterior condition of the digestive apparatus is strongly influenced by the state of the other organs of the system.

314. _Food should not be taken immediately after severe exertion, either of the body or mind._ For all organs in action require and receive more blood and nervous fluid, than when at rest. This is true of the brain, muscles, and vocal organs, when they have been actively exercised. The increased amount of fluid, both sanguineous and nervous, supplied to any organ during extra functional action, is abstracted from other parts of the system. This enfeebles and prostrates the parts that supply the blood and nervous fluid to the active organ. Again, when any organ has been in vigorous action for a few hours, some time will elapse before the increased action of the arteries and nerves abates, and a due supply of fluids is transmitted to other organs, or an equilibrium of action in the system is restablished.

315. Thus food should not be taken immediately after severe mental labor, protracted speaking, continued singing, or laborious manual toil; as the digestive organs will be in a state of comparative debility, and consequently unfit to digest food. From thirty to sixty minutes should elapse, after the cessation of severe employment, before food is taken. This time may be spent in cheerful amus.e.m.e.nt or social conversation.

_Observation._ The practice of students and accountants going immediately from severe mental labor to their meals, is a pernicious one, and a fruitful cause of indigestion and mental debility. The custom of farmers and mechanics hurrying from their toil to the dinner-table, does much to cause dyspepsia and debility among these cla.s.ses in community.

313. Should the condition of the system be regarded in taking food?

314. When should food not be taken? Why? What is the result when an organ has been in vigorous action? 315. After the cessation of severe toil, how much time should expire before eating? What is one cause of indigestion among students and accountants?

316. _Severe mental or manual toil should not be entered upon immediately after eating._ As there is an increased amount of blood and nervous fluid supplied to the stomach and alimentary ca.n.a.l during the digestion of food, a deficiency exists in other organs. This is evinced by a slight paleness of the skin, and a disinclination to active thought and exercise. Under such circ.u.mstances, if either the mind, vocal organs, or muscles are called into energetic action, there will be an abstraction of the necessary amount of blood and nervous fluid from the stomach, and the process of digestion will be arrested.

This will not only cause disease of the digestive organs, but chyle will not be formed, to nourish the system.

_Ill.u.s.tration._ An English gentleman fed two dogs upon similar articles of food. He permitted one to remain quiet in a dark room; the other he sent in pursuit of game. At the expiration of one hour, he had both killed. The stomach of the dog that had remained quiet was nearly empty. The food had been properly changed and carried forward into the alimentary ca.n.a.l. In the stomach of the dog that had used his muscles in chasing game, the aliment remained nearly unaltered.

317. The same principle may be applied to the action of the organs of man. If his mind or muscles act intensely soon after eating, the stomach will not be sufficiently stimulated by blood and nervous fluid to change the food in a suitable period. The Spanish practice of having a "siesta," or sleep after dinner, is far better than the custom of the Anglo-Saxon race, who hurry from their meals to the field, shop, or study, in order to save time, which, in too many instances, is lost by a sense of oppression and suffering which soon follows.

316. Why should not severe manual or mental exertion be made immediately after eating? State the ill.u.s.tration. 317. May this principle be applied to the action of the human stomach? What is said of the Spanish custom of resting after dinner?