The Hygienist does not agree with the thought of physiologists that salivary and gastric digestion are unimportant. The thoroughness with which enzymes do their work depends upon the amount of time they have in which to work. The several enzymes of the pancreatic and intestinal juices that complete the digestion of proteins, carbohydrates and fats in the intestine, function only in an alkaline medium. The chyme from the stomach is acid, but bile from the liver and the pancreatic juice, both of which are alkaline, quickly provide an alkaline environment for the action of the enzymes in the intestine. We need not concern ourselves with combinations, as they relate to intestinal digestion, except to point out that the best preparation for intestinal digestion is good salivary and gastric digestion.
Food combining is, therefore, of greatest important as it relates to salivary and gastric digestion.
The same test may be performed with a combination of starches and proteins-the extraction of parts of chyme at intervals, as they happen during our digestion, will always show this arrest of ptyalin digestion, meaning that the starches then unsplit will never be properly split. Three Philadelphia investigators studied five subjects. The investigation clearly showed that when high starches and high proteins are mixed at one meal, there is too much acid to permit the continued alkaline reaction of the starch part, and not enough acid to start the digestion of the protein part. When foods are eaten in compatible mixtures, and the efficiency of digestive enzymes is reduced and inhibited, the food is subject to decomposition in the digestive tract. The sugars in sweet fruit are apt to ferment if digestion is delayed.