R. H. Chittenden

“ Imagine, if you will, the concrete case of a man of 70 kilos body-weight eating a daily ration containing 125 grams of proteid, the nitrogen equivalent of which is practically excreted within twenty-four hours, and are we not wise in hesitating to believe that all of that proteid has been so quickly built up into living or organized tissue only to be immediately broken down and thrown out of the body? ”

“ The master words which promise help in the carrying out of an intelligent plan of living are moderation and simplicity; moderation in the amount of food consumed daily, simplicity in the character of the dietary, in harmony with the old saying that man eats to live and not lives to eat. In so doing there is promise of health, strength, and longevity, with increased efficiency, as the reward of obedience to Nature’s laws. ”

“ Proteids are confessedly among the most complex bodies the physiologist has to deal with, while at the same time they are perhaps the most important, not only in view of their wide-spread distribution through animal and vegetable tissues, but because of the prominent part they take in the nutrition of the body. The more our knowledge is broadened concerning these varied substances, the more we are impressed with their complexity, and at the same time with the necessity for a more accurate study of both their composition and constitution. ”

“ The man whose work is mainly mental has no real need for high fuel values in his daily ration. For such a man, a high potential energy in the daily intake of food is an incubus and not a gain. Body equilibrium can be maintained on far less than 3000 calories per day by the brain worker, and in the interest of health, strength, and vigor, as well as scientific truth, why teach the doctrine that a healthy man needs, on an average, foodstuffs to furnish 3000 calories or more per day, with 16 to 18 grams of nitrogen in the form of proteid? ”

“ One cannot fail to be impressed with the resemblance in functional power between the unformed ferments as a class and cell-protoplasm. To what can we ascribe the particular functional power of each individual ferment? Why, for example, does pepsin act on proteid matter only in the presence of acid, and trypsin to advantage only in the presence of alkalies? Why does pepsin act only on proteid matter, and ptyalin only on starch and dextrins? Why does trypsin produce a different set of soluble products in the digestion of albumin than pepsin does? ”

“ There are many suggestions of improvement in bodily health, of greater efficiency in working power, and of greater freedom from disease, in a system of dietetics which aims to meet the physiological needs of the body without undue waste of energy and unnecessary drain upon the functions of digestion, absorption, excretion, and metabolism228 in general; a system which recognizes that the smooth running of man’s bodily machinery calls for the exercise of reason and intelligence, and is not to be intrusted solely to the dictates of blind instinct or to the leadings of a capricious appetite. ”

“ Here, then, we have suggested a radical change in diet which experiment shows is perfectly safe, and we are disposed to urge that there is great systemic value, both in health and in many forms of disease, in such a change. It is obvious, as previously stated, that the smallest amount of food that will serve to maintain bodily and mental vigor, keep up bodily strength, and preserve the normal powers of resistance to disease, is the ideal diet. Any excess over and above what is really needed for these purposes imposes just so much of an unnecessary strain upon the organism. ”

“ To-day, as a nation, we have greater wealth, and our commercial prosperity has become phenomenal; but would any one think for a moment that these characteristics are attributable to the large consumption of proteid food so common to this generation of the American people? No, increased wealth simply paves the way for greater freedom in the choice of food ”

“ Physiological economy in nutrition means temperance, and not prohibition. It means full freedom of choice in the selection of food. It is not cereal diet nor vegetarianism, but it is the judicious application of scientific truth to the art of living, in which man is called upon to apply to himself that same care and judgment in the protection of his bodily machinery that he applies to the mechanical products of his skill and creative power. ”

“ If it is true that the demands of the body for proteid food—which of all foods is the most expensive—are fully met by an amount equal to one-half that ordinarily consumed, and that health and strength are more satisfactorily maintained thereby, it is easy to see how the acquisition of dietary habits leading to consumption of food in harmony with physiological needs will result in a fruitful twofold economy; viz., economy in expenditure, and of still greater moment, economy in the activities of the body by which food and its waste products are cared for. ”

“ Far more rational is temperance in place of prohibition, and I am inclined to emphasize the systemic value of a daily diet so reduced in quantity that the metabolic processes may be largely decreased, in closer harmony with true physiological needs, especially those which involve the breaking down of proteid matter; and in making this suggestion I can add the assurance, based upon these observations on many individuals, that there is not only perfect safety but gain to the body, in diminishing proteid metabolism to a level somewhere near the actual requirements of the individual. ”

“ Do not the cravings of the stomach and the so-called pangs of hunger merit consideration? Is it not the part of wisdom to follow inclination in the choice and quantity of our food? Can we not safely rely upon these factors as an index of the real needs of the body? If these questions are to be answered in the affirmative, then it is plain that a study of dietetic customs will tell us definitely how much food and what kinds of food are required daily to supply the true wants of the body. There are writers who claim that instinct is a perfectly safe guide to follow ”

“ Dietary standards at the best are merely an approximate indication of the amounts of food needed by the body, but these needs are obviously changeable, varying with the degree of activity of the body, especially the amount of physical work performed, to say nothing of differences in body-weight, sex, etc. Further, it is doubtless true that there is what may be called a specific coefficient of nutrition characteristic of the individual, a kind of personal idiosyncrasy which exercises in some degree a modifying influence upon the character and extent of the changes going on in the body. ”

“ With a diet restricted to one or two vegetable products, it is quite conceivable that something may be lacking which the system demands, though it cannot be measured in terms of nitrogen or calories. It may be said that man thrives on a purely vegetable diet, but while this is unquestionably true, it must be remembered that man with his free choice of food has recourse, as a rule, to a large variety of vegetable products from many sources, and consequently there is great likelihood of his absorbing from these varied products such supplementary matters as may be needed. ”

“ On matters of diet every man should be a law unto himself, using judgment and knowledge to the best of his ability, reinforced by his own personal experiences. Vegetarianism may have its virtues, as too great indulgence in flesh foods may have its serious side, but there would seem to be no sound physiological reason for the complete exclusion of any one class of food stuffs, under ordinary conditions of life. ”

“ Simplicity of diet, however, does not diminish but rather increases the pleasure of eating, especially when daily restriction in diet—indulged in until a new habit is formed—has created a greater keenness of appetite, since under such conditions the palate takes on a new sensitiveness, and manifests a fuller appreciation of the variations of even a simple dietary. There is therefore no hardship, nor curtailment of the pleasure of eating in the restriction of the diet to the real needs of the body. ”

“ Truly, we might just as well argue that this significant rise in the excretion of nitrogen after partaking of a proteid meal is an indication that the body has no need of this excess of nitrogen; that it is indeed a possible source of danger, since the system strives vigorously to rid itself of the surplus, and that the energy-needs of the body can be much more advantageously and economically met from fat and carbohydrate than from the carbonaceous residue resulting from the disruption of the proteid molecule. ”

“ Among the various conditions that influence the energy exchange of the body, muscle work stands out as the most conspicuous. It needs no argument to convince one that all forms of muscular activity involve liberation of the energy stored up in the tissues of the body; and consequently that all work accomplished means chemical decomposition, in which complex molecules are broken down into simple ones with liberation of the contained energy, the energy exchange being proportional to the amount of work done. ”

“ How far can our natural instinct be trusted in the choice of diet? We are all creatures of habit, and our palates are pleasantly excited by the rich animal foods with their high content of proteid, and we may well question whether our dietetic habits are not based more upon the dictates of our palates than upon scientific reasoning or true physiological needs. ”

“ In other words, is a low proteid diet, one that seems sufficient to maintain the body in nitrogen equilibrium, a wholly safe one to follow? May there not be other elements to be considered, aside from nitrogen equilibrium, which, if fully understood, would satisfactorily account for the customs of mankind, in which perhaps man’s instincts have been followed for the betterment of the race? ”

“ If it is true, on the other hand, that the healthy organism needs a daily intake of 118 grams of proteid food more or less, in order to maintain physiological equilibrium, to keep up physical and mental vigor, and to preserve the normal power of resistance to the incursions of disease, then we must consider that the good overbalances the evil, and that evil exists in order that good may be accomplished. ”

“ There is no apparent reason why maltose should not be absorbed and assimilated as readily as dextrose, but so urgent is the necessity for this conversion into dextrose that in the blood itself there is present maltase, to effect the transformation of any maltose that may gain entrance there. We are here face to face with a simple fact in nutrition. The body cannot utilize disaccharides directly. Why it is so we cannot say, but the fact is a good illustration of the principle that nothing can be taken for granted in our study of nutrition. ”

“ Physiological economy, as the writer defines it, is not prohibition, but temperance. Moderation in diet, especially in the taking of proteid foods, means a great saving in the wear and tear of the body machinery. It must presumably mean greater freedom from many diseases in which individual organs, such as the liver and kidneys, are frequently involved. It suggests, likewise, greater freedom from many disturbances of general metabolism which eventually terminate in a perversion of nutrition, so marked as to constitute a serious condition of disease. ”

“ There is no occasion, unless one finds pleasure and satisfaction in so doing, to resort to a limited dietary of nuts and fruits, to become an ardent disciple of vegetarianism, to adopt a cereal diet, to abjure meats entirely, or to follow in an intensive fashion any particular dietary hobby, except so far as may be necessary to insure an adequate amount of non-nitrogenous foods to meet the energy requirements of the body without unduly increasing the intake of proteid or nitrogenous food. ”