Protein Starch Combinations

Article #4: Protein-Starch Combinations by Dr. Herbert M. Shelton

At frequent intervals, some chemist or physician comes forward with the announcement that there is nothing to the idea that people have better health if they do not combine starch and protein foods in the same meal. They are sure to tell us that laboratory experiments show that digestion is carried out almost as quickly where these foods are combined as where only one is taken at a time. They are likely to add that experiments with certain patients verify this opinion of theirs.

We have in these announcements, two groups of men invading a field and posing as authorities therein, to which they are alien. Chemists know nothing of feeding man or animal. They should stick to chemistry. Physicians are not trained in dietetics. They know nothing of feeding the well and the sick. They are trained in the black art of poisoning the sick. I will not say that they should stick to this practice, but I will say that they should cease trying to pass themselves off on the public as authorities in fields outside their own.

Of what value are their laboratory experiments? Very little. A laboratory is not a human being. It is not a human digestive tract. The laboratory experiment cannot be substituted for the actual work of digesting a meal. Even feeding test meals and pumping out the stomach contents, or viewing the stomach through the X-ray is not a satisfactory approach to the solution of the problems involved in the heterogeneous and haphazard mixtures of foods commonly consumed at a meal.

What can be learned from feeding one meal to a subject, or even from feeding a few such meals to a few subjects? One such meal may not bring any distress to the subject. Indeed, we see many people eating such meals regularly for years before they develop discomforts therefrom. But the constant repetition of heavy protein-starch meals taxes their digestion to the limit and, sooner or later, results in discomforts and diseases galore.

Dr. Tilden once pointed out that nearly all such experiments are carried out by physicians and chemists who use the potato as the starchy part of the diet, and, he adds, “I have often stated, the potato is the least objectionable of any starch to be used with protein, on account of its potash content.” My own view is that the potash content of the potato is not concerned in the matter at all. Potato starch digests in ten minutes under ideal conditions. I am of the opinion that it is the rapidity with which the potato starch digests that makes its combination with protein less objectionable than the combination of other starches with protein. It seems to be that the potato starch digests before the gastric juice of the stomach can accumulate in such quantity as to materially interfere with the digestion of the starch. Whatever the true explanation, the fact still remains that potato with protein, though objectionable, is less so than some other starchy foods with protein.

The man who has fed thousands of patients, old and young, and has had an opportunity to study the effects of diets and food combinations upon the health and diseases of these people is in a far better position to judge the accuracy of the contention that protein-starch combinations are not conducive to good digestion and good health, than are the chemists who feed nobody and the physicians whose great work is that of poisoning the sick.

Those of us who have made these observations know well that correct food combinations result in an immediate improvement in health by lightening the load the digestive organs have to carry. We know that we see better digestion and less fermentation and putrefaction. We see more comfort and less distress. There is less gas and little or no odor to the gas.

I do not believe that such experiences are worth anything if they cannot be explained by correct principles. Unless they can be explained by the facts of physiological chemistry, particularly the chemistry of digestion, we may be only deluding ourselves. On the other hand, if our rules of food combining are soundly rooted in physiology, they are worthy of more than a passing notice.

It is frequently objected that nature, herself, combines starches and proteins and if nature does, we may do so also. This objection is not valid. It is based on the untenable assumption that everything in nature is designed or intended for food. The great representative examples of protein-starch combinations in nature are cereals and legumes. These are the very foods that are most prone to decompose in the digestive tract when eaten. Neither of them constitute the best of foods and neither of them is readily digested. While a diet of cereals or a diet of legumes is inadequate in several ways, there is reason to believe that some of the inadequacies that result from such dietaries are results of the failure of digestion, a failure that is probably the result of the protein-starch combination.

Physiologically, the first steps in the digestion of starches and proteins take place in opposite media—starch requiring an alkaline medium, protein requiring an acid medium in which to digest. The enzyme ptyalin (salivary amylase) that initiates starch digestion is active in an alkaline medium only and is destroyed by a mild acid. On the other hand, pepsin, the enzyme that initiates protein digestion is active only in an acid medium. If starches and proteins are eaten together, the acid gastric juice destroys the ptyalin and puts an end to salivary digestion of starch. That the presence of the undigested starch in the stomach interferes with the digestion of protein is shown by the presence of undigested protein in the stools. Physiologists have shown that undigested starch absorbs pepsin and this will surely interfere with digestion of protein.

If a food that is a natural protein-starch combination is eaten alone, the body is capable of modifying its digestive juices and timing their secretions in such ways that digestion can go on with a fair degree of efficiency. But when a starch food and a protein food are eaten at the same meal this precise adaptation of the digestive secretions to the character and digestive requirements of the food is not possible. There is a marked and important difference between eating a food that is a natural protein-starch combination and eating two foods, one a protein, the other starch.

When starches and proteins are eaten together, there is a fermentation and this results in fouling the whole digestive tract. Fermentation means irritation and poisoning. If starch is eaten without protein, the gastric (stomach) secretions will not be acid, or will be so weakly acid that they will not interfere with salivary digestion. In this case here will be no fermentation, except from other causes, such as overeating, hurried eating, other wrong combinations, eating when fatigued, worried, angry, fearful, grieved, etc., eating immediately before beginning work, eating when in pain, fever or when there is inflammation, etc. The causes of indigestion are legion.

When the artificial protein-starch combination is eaten, not only undigested starch, but undigested protein will be found in the stools. The presence of undigested starch and protein in the stools is of far greater importance in determining the digestibility or indigestibility of a food combination than is the emptying time of the stomach. “Research” workers have found that the protein-starch combination delays the digestion of protein four to six minutes. This would seem to be unimportant, and I believe it is unimportant. If this brief delay in protein digestion represented all there is to the matter, we could forget the whole thing and continue to eat haphazardly. But starch digestion is important, also. Then there is the fact that the delay in emptying time of the stomach is no criterion of the completeness with which gastric digestion of protein has been done.

Physiologists resort to a number of “dodges” to escape the obvious implications of the facts of the physiology of digestion. A fine example of this is contained in Physiology by V.H. Mottram, professor of physiology at the University of London. He says that when the food in the stomach comes in contact with the gastric juice no salivary action is possible. He says: “Now gastric juice digests protein and saliva digests starch. Therefore it is obvious that for efficient digestion the meat (protein) part of a meal should come first and the starchy part second—just indeed as by instinct is usually the case. Meat precedes pudding as being the most economical procedure.”

Why should it make any difference what order in which we consume the various foods at a meal? Mottram explains it in this way: “the distal end of the stomach is that in which the churning movement that mixes the food with gastric juice takes place … But the food in the quiescent end is still under the influence of the saliva, while the food in the motile end comes into contact with the acid gastric juice and no salivary action is possible.”

This means that if you eat your protein first so that it will be down in the lower end of the stomach and consume your starch last so that it will be in the upper part of the stomach, the protein will be digested below while the starch is digested above.

Assuming that there is any absolute demarkation between the food in the different parts of the stomach, and this assumption would be false, it is still not true that people in general, either instinctively or otherwise, consume their proteins and starches in this manner. Perhaps in England it is customary to eat meat at the beginning of a meal and pudding at the end, just as we have a similar practice of taking a dessert at the end of a meal in this country; but it is likely to be the practice there as here of eating bread and meat together. When the average man and woman eats flesh or eggs, or cheese, he or she takes bread with the protein. In eating hamburgers, sandwiches, hot dogs and similar dietetic abominations, it is certainly not the custom to consume the protein first and then, at the end of the “meal” eat the bun or other bread. The protein and starch are eaten together and are thoroughly mixed in the mouth in the process of chewing before they are swallowed.

For good digestion, let us eat our proteins and starches at separate meals.