Digestion

“ When we reflect that the object of digestion is to furnish materials for the growth of the body, and to supply the waste which the system is constantly undergoing, it must appear self-evident, that, if the digestive powers be impaired by disease, by improper quantity or quality of food, or by any other cause, the result must necessarily be the formation of an imperfect chyle, and consequently of imperfect blood. ”

“ When we are exerting the muscular system for a long time in some laborious employment, how else are our members to inform the stomach that they are too much occupied with their duties to spare the blood necessary in digestion; that it is requisite that the appetite should decline; and that digestion should cease for the time, even if the stomach should be oppressed with its contents? When we are thinking, how else are the blood-vessels to be told that an unusual supply of their contents is wanting in the head? ”

“ In a mixed ration, consisting of several articles of food of different mechanical structure, the work of digestion is more evenly distributed among the various organs. A food often requires special preparation on the part of the stomach before it can be digested in the intestines, and if this food is consumed in small amounts and combined with others of different structure, the work of gastric digestion is lessened so that the foods are properly prepared and normal digestion takes place. The effect which one food exerts upon the digestibility of another is largely mechanical. ”

“ Digestion is that act by which the aliment or food is prepared, so as to produce a good chyle, and consequently good blood, for the nourishment of the body. Though no animal has a more delicate stomach than man, yet it must be observed, that none has a stomach better adapted for all kinds of food. ”

“ Hygiene of Digestion.—With the stomach and other digestive organs in a state of perfect health, one is entirely unconscious of their existence, save when of feeling of hunger calls attention to the fact that food is required, or satiety warns us that a sufficient amount or too much has been eaten. Perfect digestion can only be maintained by careful observance of the rules of health in regard to habits of eating. ”

“ Adjuvants to Digestion.—In atony of the stomach the gastric mucous membrane responds feebly to the stimulus of food. There is failure in both muscular movement and gastric secretion, with slowness of digestion as a result. To meet this condition we seek to increase the digestive power by the addition of certain principles natural to the digestive process—viz. the mineral acids, pepsin, and pancreatin. Of these acids, the hydrochloric should be preferred, because it is the natural acid of the gastric juice. ”

“ Many people, from want of any better occupation, make a pastime of filling their stomachs every forenoon at the pastry-cook’s, with as little regard to its powers and necessities as if digestion were meant merely as an appendage to taste; and think themselves entitled to complain of their defective appetites, and the great discomfort which attends the subsequent ingestion of a heavy dinner. To relieve the weakness, arising not from exhaustion but from the oppression of satiety, they resort to wine, as if by adding fuel to the fire they could hope to extinguish the flame! ”

“ Starch and warm water alone under similar conditions will not react to the test for grape sugar.
Digestion has the Same Purpose in Plants and Animals.—In our own bodies we know that solid foods taken into the mouth are broken up by the teeth and moistened by saliva. If we could follow that food, we would find that eventually it became part of the blood. It was made soluble by digestion, and in a liquid form was able to reach the blood. Once a part of the body, the food is used either to release energy or to build up the body. ”

“ Factors Influencing Gastric Digestion.—The factors influencing digestion in the stomach constitute all those mechanical, electrical, chemical, and psychical factors which stimulate or retard the action of the gastric juices. The movements in the stomach are involuntary, but their activities may be stimulated by the flow of gastric juice. Sleep retards digestion in the stomach by retarding the movements in the organ itself. ”

“ Before, however, commencing a description of the organs concerned in digestion, it will be useful to take a general view of the different stages of preparation through which the food passes, between its reception into the stomach and its assimilation, or ultimate conversion into a constituent part of the animal body, and becoming endowed with the properties of life. ”

“ Digestion is performed slowly in men of learning, therefore fresh aliments should seldom be given them; because the state of the stomach is very different when it is half full of undigested aliments, from what it is when entirely void of aliments, and overflowed with the gastric fluids, ready for the use of concoction. ”

“ At that age the teeth and other organs concerned in digestion [275] have become developed and fit for the assimilation of a richer aliment, and the rapid growth which takes place renders an abundant provision of the latter in a manner indispensable. It is then that the healthy youthful appetite demands quantity as well as quality, and that digestion goes on with an ease and vigour which the dyspeptic parent contemplates with a covetous and regretful eye. ”

“ And as the whole process of digestion and assimilation is, according to the most attentive observers, performed in about four hours, if the stomach has not been unnaturally distended by superfluous food, it follows, that it is contrary to the order of Nature, to swallow a larger quantity of provisions, at one meal, than we are able to digest during that time. ”

“ Any change in diet that carries with it the persuasion that for any reason digestion ought to be better, will, because of this, make digestion better. Any habit of taking warm or cold water before meals, or of chewing in a particular way, or of taking a particular kind of food different from what is usually taken—exclusively cereal, uncooked, largely fruit, vegetarian, etc.—will lift the concentration of attention on the digestive process, and so give the stomach a chance to do its work without interference from the brain. ”

“ How very powerful a human stomach may sometimes be, and how large a task in the way of digestion it may sometimes perform without complaint, is known to those who have had the opportunity of observing what certain persons with exceptional power are accustomed to take as food, and do take for a long time apparently with impunity. But these are stomachs endowed with extraordinary energy, and woe be to the individual with a digestive apparatus of moderate power who attempts to emulate the performance of a neighbor at table who perchance may be furnished with such an effective digestive apparatus! ”

“ To he fully acquainted with digestion, one must know hoth its antecedents and consequents.
INGESTION. Appetite, hunger, and thirst, warn us that the hody needs restoration; pain, that universal monitor, never ceases to torment us if we do not obey it.
Then comes eating and drinking which are ingestion, an operation which begins as soon as the food is in the mouth, and enters the oesophagus. ”

“ There are some persons constituted with such vigorous powers of digestion that no quantity of food oppresses their stomachs. If they eat habitually more than what is required to supply waste and sustain the system, they speedily suffer from repletion, or some one or other of the diseases arising out of its existence, such as inflammation, apoplexy, rupture of bloodvessels, enlargement of the heart, or morbid growth in some organ of the body. ”

“ Not only that the progress of digestion is thus interrupted, not only that the body derives no strength from the inert mass of ingesta, but that mass, by undergoing a putrid instead of peptic decomposition, vitiates the humors of the system it was intended to nourish, irritates the sensitive membranes of the stomach, and gradually impairs the vigor of the whole digestive apparatus. ”

“ Digestion signifies the act of separating or distributing, hence its application to the process by which food is made available for nutritive purposes. The organs of digestion are the Mouth, Teeth, Tongue, Salivary Glands, Pharynx, Esophagus, the Stomach and the Intestines, with their glands, the Liver, Pancreas, Lacteals, and the Thoracic Duct. ”

“ By loading the stomach, digestion is impeded; for the natural juice of the stomach, which is the great medium of digestion, has not then room to exert itself. The stomach therefore nauseates its contents, and is troubled with eructations; the spirits are oppressed, obstructions ensue, and disease is the consequence. Besides, when thus overfilled, the stomach presses on the diaphragm, prevents the proper play of the lungs, and occasions difficulty and uneasiness in breathing. ”

“ Intestinal Digestion.—The chemical changes which food undergoes in the small and large intestines are exceedingly complex. Digestion in the intestine is due to the combined action of the bile, pancreatic juice, and succus entericus. The material which enters the duodenum from the stomach is known as the chyme. The acid chyme provokes a flow of bile and pancreatic juice. It acts upon the prosecretin in the duodenal mucous membrane in such a manner that secretin, a hormone, is formed and carried by the blood to the cells of the pancreas which it stimulates. ”

“ Our forefathers considered the stomach the all-important organ of digestion and the intestines as scarcely more than a long tube to facilitate absorption and deal properly with waste materials. Their relative values are now exactly reversed in our estimation. The stomach has come to be looked upon as scarcely more than a thin-walled bag meant to hold the food that we take at each meal and then pass it on by degrees to be digested, prepared for absorption and finally absorbed in the intestines. ”

“ All or nearly all of the energy-yielding foods, on the other hand, must have a preliminary preparation to which we give the name of digestion; the operation of digestion being to break down the complex foodstuffs that are eaten into simpler materials of which the body can make use. Digestion is made up of a series of chemical changes by which the large molecules of the original foodstuffs are broken into smaller and simpler molecules. This breaking down of large molecules into smaller is a very common kind of chemical process. ”

“ If what Taste rejects, after having selected nutriment out of a morsel of [Pg 199] food is dirt, WHAT SENSE is there in allowing it to contaminate and burden the delicate organs of digestion?
An indigestible morsel of food is like a runaway team in a crowded street. WHAT SENSE is there, then, in demoralising things in the thoroughfare of our life organism by admitting unruly substance?
An indigestible morsel of food in the stomach, and all the way through the intestines, is like a "bull in a china shop." ”

“ I believe that every stomach, not actually impaired by organic disease, will perform its functions if it receive reasonable attention; and when we consider the manner in which diet is generally conducted, both in regard to quantity and to the variety of articles of food and drink which are mixed up into one heterogeneous mass, instead of being astonished at the prevalence of indigestion, our wonder must rather be, that, in such circumstances, any stomach is capable of digesting at all. ”

“ There are others that make the Stomach itself to be the great Instrument of Digestion, but in a different manner: And they suppose it to be perform'd by an Attrition, as if the Stomach, by those repeated Motions, which are the necessary Effects of Respiration, when it is distended by the Aliment, did both rub or grind off some minuter Particles from the grosser Parts; and by continually agitating the Mass of Food, make those Parts, which are not contiguous to the Stomach, strike one against another, and break one another in pieces, until they are all attenuated. ”

“ The chyme leaving the stomach, enters the small intestine, as we have described and comes in contact with the pancreatic and intestinal juices and with the bile, and intestinal digestion ensues. These fluids dissolve most of the food that has not already been softened. ”

“ The stomach accustomed for a time to the smallest quantity, is no longer able to provide gastric juice sufficient for the purposes of digestion; and being irritated by continued craving, its secretions are vitiated and its sensibility exalted to such a degree as to require the wisest management to enable it to regain its healthy tone. ”

“ The motion which we have seen to be excited in the stomach by the entrance of aliment, is at first very gentle and slight; but in proportion as digestion proceeds, or the organ is distended, it becomes more rapid and energetic; and then it serves the additional purpose of gradually propelling the chyme through the pylorus into the intestine, there to be farther prepared and converted into chyle. The necessary churning or agitation of the food is, from the peculiar situation of the stomach, greatly assisted by the play of the diaphragm and abdominal muscles during inspiration and expiration ”

“ Healthy stomach digestion requires at least five hours for its completion, and the stomach should have an hour for rest before another meal. If fresh food is taken before that which preceded it is digested, the portion of food remaining in the stomach is likely to undergo fermentation, thus rendering the whole mass of food unfit for the nutrition of the body, besides fostering various disturbances of digestion. ”