HEALTH COLUMN.

Otago Witness, Issue 3169, 9 December 1914, Page 73

HEALTH COLUMN.

DIGESTION AND HEALTH. The digestive organs have so much to do with our health in general that it is incumbent upon us all to know some of the essential facts pertaining to the digestion of food. Even an elementary knowledge of the digestive function is helpful to all, by showing how to avoid dietetic pitfalls. Stages of Digestion.— Let us first take a brief survey of the stages of digestion, and, secondly, point out how this knowledge may bo applied to our daily lives. Digestion may be conveniently divided into three stages—first, digestion in the mouth; secondly, digestion in the stomach; and, thirdly, digestion in the intestine. Digestion in the Mouth. — By most people digestion is supposed to begin and end in the stomach. That this is far from being the case wo shall new learn. One of the most important rules of health in relation to digestion is the care and use of the teeth; yet, judging from the way food is usually bolted, one might almost suspected that they never existed at all. The amount of dyspeptic troubles that is suffered from having teeth that arc insufficient masticators, and from the non-usage of good teeth, is enormous. The mastication of food is exceedingly important, for it not only helps to keep the teeth in a healthy state, but it considerably lightens the work of the stomach. The Saliva. — There is scarcely any fluid that we are more careless about than the saliva of the mouth, and yet this fluid is of extreme importance in digestion. This saliva has many purposes. It is necessary for speech; by dissolving substances, it helps taste ; it helps cwallowing by moistening food, and, lastly, it has a special chemical action on some foods. Saliva contains a special ferment (ptyalin), which converts starch into grapesugar. Now, all starchy foods have to undergo this change before being of use to the body ; so bolting food becomes injurious, among other reasons, because those starchy foods escape the conversion they should undergo. Here we should note that the saliva of infants under nine months contains practically no ptyalin, and cannot, therefore, thus convert starch. Ignorance ot this fact among mothers who give their little ones bread sojis, etc., causes much harm, as diseases of various kinds must surely follow such a diet. Digestion in the Stomach.— The food having been swallowed, wo must turn our attention to what goes on in tile stomach. vVhen food enters the stomach, increased blood-flow is at once seen in that organ, while from the small glands which lie in the walls a digestive juice is poured out. This juice when analysed is found to contain many substances, the most characteristic being a ferment called “pepsin.” This ferment acts principally on n.trogenous food, and with the help of hydrochloric acid, which is also found in the stomach, converts it into substances known as “ peptones,” and unless the nitrogenous food is so altered, it cannot be absorbed into the blood. The stomach appears to have no power of digesting starch, fats, or sugars. The stomach now churns the food about until a semi-liquid mass results, known as “chyme.” This chyme is now driven into the intestine, where it becomes mixed with bile and the pancreatic juice. The bile docs not play a very important role in digestion; it has an antiseptic action on the contents of the bowel, emulsifies fats, and tends to promote the onward movements of the intestines. The pancreatic juice is very important, for it is the chief element in digesting fats, while it has also an action on the starches and sugars, and eo supplements the action of the saliva. It also contains a special ferment which completes what the gastric juice did —namely, the conversion of nitrogenous food into peptones. Should these digestive processes not be properly carried out, half-way products are liable to bo formed, which get absorbed into the blood, and there give rise to the various symptoms which may characterise indigestion, while fermentation is liable to take place, giving rise to evolution of gases, thus causing flatulence. The contents of the intestine, now known as “ chyle,” are propelled along by the muscles in the walls of the bowel, and become gradually absorbed. Previous to absorption, digestion is often completed by the action of bacteria, but exactly what action thus takes place is not known. - Our Duty.— Having now given a brief sketch of the process of digestion, it remains for ns to see how we may use this knowledge to avoid indigestion and other ailments. Wo can now see the importance of mastication, in order to convert nil starchy material into sugar, for, as hoa boon stated, the stomach is not capable of dealing with it, and the flooding of the stomach with starchy foods is a fruitful cause of dyspepsia in old and young. The gastric juice naturally finds it difficult to act upon a lump of food that has not been properly disintegrated by the teeth. Rest after meals is another factor to be thought, of, for blood cannot be in two places at the same time, and, as so much is required in the region of the stomach, it can only do harm to indugo in physical exercise which drives blood to the limbs. The same applies to mental work, for then blood is bound to bo called to the brain, which ought to be aiding digestion below. Drink should only be taken towards the end of a meal, and then the less taken the hotter, for, it the digestive juices arc not diluted, they can, of course, perform their work more efficiently. Drinking tea with meat is certainly a habit most prejudicial to digestion, so that the somewhat prevalent hab't of having “meat teas” should bo avoided. Everyone should nnder-eat rather than over-eat, and the meals are best taken in company whenever possible, for the presence of pleasant company, andi the conversation that takes place, all tend to have a favourable influence on digestion. Those points may seem to many trivialities, yet taken together they make all the difference between happiness and misery, between good and bad health.