How Your Digestion Works

By Frank W. Britton, D.S.C.
The most important factor in the life of the animal organism is nutrition, and nutrition cannot be perfect without a healthy set of digestive apparatus.
It is important to recollect that a proper selection of food is absolutely essential to the normal health of the organs employed in digesting it. Therefore great attention should be paid to feeding itself –that is to mastication, for this seems to be the only digestive process well within our control.
Some of us are what are sometimes termed “quick eaters” –very often an enforced and unfortunate habit – a fact which makes for indigestion more than anything perhaps, owing to the swallowing of too large a quantity of undigested starchy food. Of course, an appetite for savory dishes might easily account for the more usual varieties of indigestion –that may be the cause of the incidence of the complaint around Christmas time. It is as well, then, to know something about the organs concerned and the destiny of our food during the process of digestion.
Physiologically, the long tube or alimentary canal through which the food passes is an entirely separate system form the rest of the body, although in close association with it and functioning as a “feeder” for nourishing the vital organs.
This long “feeder” becomes dilated at such portions of its length, as at the stomach, and twisted at others, as in the folds of the intestines. However, the fact is emphasized that such s system must maintain a high degree of integrity or co-operative function in order to permit of the essential elements of our food reaching the glands and organs of the body.
Now this “integrity” is shown in the dependence of one set of organs upon another, and can be only perfectly normal provided that each set does its work satisfactorily –otherwise the economic system of the body will suffer. It is just like the ordinary political economy of the State in which each member participates and builds up one harmonious organization.
Importance of Mastication
Mastication is concerned with the teeth. These bodies deal with the first process of digestion, for they grind and crush the larger portion of our food under the leverage of the jaws –this constitutes mastication proper.
Such a process induces a flow of saliva, so that the food is mixed with an alkaline fluid and a ferment which converts the starches of the food into sugar. This fact is very important, for the carbohydrates are here first acted upon and rendered digestible –all starchy foods should therefore be well chewed.
Since the bulk of our food consists of materials like bread, potatoes and farinaceous stuff, we should pay more attention to their proper treatment in the mouth. In this way, less work is imposed upon the stomach and small intestines, for we must remember that the latter are called upon the compensate for the little indiscretions of mastication, such as when we are in so great a hurry that we “bolt” our meals.
Action of the Stomach Juices
The second stage in the digestive is swallowing or deglutition. After we have swallowed our food it enters the alimentary canal, passing thence to the stomach.
Here the albumens of the food –those contained in meat, eggs, etc., and also termed proteins –are acted on by a weak acid secretion, gastric juice and a ferment called pepsin, and are converted from insoluble substances into soluble bodies called peptones
The peptones pass very readily through the membranes of the intestines into the series of absorbent vessels which surround them, the lacteals and lymphatic glands. So we see that the stomach, if functioning normally, deals with the proteins of the food and renders them soluble and fit to be taken into the blood.
Now we pass to the small intestine which leads from the stomach via the tube called the duodenum. In passing through the duodenum the semi-fluid food is attacked by two very important juices or secretions, one form the gall-bladder (bile), the other from the pancreas (amylopsin). We will see the action of these two fluids.
The Duodenal Fluids
Bile is the product of the liver and is stored in the gall bladder until called forth under the stimulus of digestion. Being strongly alkaline, it acts on the fatty acids of the undigested portions of the food and neutralizes them, rendering them soapy.
As everyone knows, soap produces a soluble lather, and in the same manner food is saponified and made soluble through the bile acting on the fatty contents. Here, then, is a rather vigorous chemical action, and it is small wonder that, if the concentration of the fluids concerned is at all great, there is an irritation sufficient to set up an ulcerated condition of this part of the digestive system.
Indeed, this is what often happens –duodenal ulcer is a more or less common complaint associated with indigestion and dyspepsia in the chronic stages.
Amylopsis is a ferment very similar to the ferment of the saliva –ptyalin –which changes starch to sugar such ferments are called diastatic ferments or enzymes.
The obvious use of amylopsin therefore is to check the danger caused by allowing unchanged starchy foods to enter the bowels, such foods having escaped without the saliva ferment having attacked them –the consequence of a hurried meal.
The body is safeguarded in having this second ferment to deal with those substances which would otherwise harm it if left undigested in the bowel. Surely it is much wise to chew all food thoroughly, thus dispensing with this piece of unnecessary overwork which takes place at a part of the anatomy which as before mentioned, is the seat of so many disorders.
Faulty Liver and Diabetes
Support for a little-known theory on the cause of diabetes came today form the Institute for Medical Research at Jewish hospital, Cincinnati, Ohio.
Dr. I. Arthur Mirsky, explaining a report he gave to the Cincinnati Academy of Medicine, disclose that investigation by himself and his colleagues had strengthened a theory that diabetes may be the result of an effort by the liver to make up a deficiency of its own carbohydrate content by producing a supplemental supply of sugar from other substances, such as fat and protein.
The studies, Dr. Mirsky said, showed that the liver converts other substances to sugar in order to supply the deficiency when it loses its own ability to retain a normal supply of glycogen. The sugar produced by the liver then enters the blood stream and the unnatural expedient produces toxic substances.
While the process continues until the sugar content of the blood reaches an abnormal high level, as a rule it does not reach the point where the physiological needs of the liver for sugar are satisfied.
Dr. Mirsky said it still is difficult to determine the fundamental causes of diabetes in individual cases but that it appeared that the same disturbance of the liver occurred in all cases.
This, he emphasized, supports a belief that diabetes, rather than being a disease in itself, is a disturbance of the liver resulting from any several causes.
Vitamin C Content of Milk
According to Heinz Ferdinand the content of cow’s milk and mother’s milk is, in the early part of the year, lower than in winter, so that at this time not only through feeding with cow’s milk but also feeding by a wet nurse a latent C-Hypovitaminosis of the nursling is to be feared. By the aid of doses of synthetic vitamin C to the wet nurse, the vitamin C content of her milk can be markedly increased and this danger avoided.
Klinische Wochenschrift, 1936-37.