R. H. Chittenden

“ 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. ”

“ 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? ”

“ 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 ”

“ 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. ”

“ 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. ”

“ 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. ”

“ 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 ”

“ The celebrated philosopher, John Locke, in his essay on education, says: “I do not think all people’s appetites are alike . . . but this I think, that many are made gourmands and gluttons by custom, that were not so by nature; and I see in some countries, men as lusty and strong, that eat but two meals a day, as others that have set their stomachs by a constant usage, like Larums, to call on them for four or five.” Again, the so-called cravings of appetite are largely artificial and mainly the result of habit. ”

“ 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. ”

“ In the absence of the particular chemical groups, the oxidase is unable to bring about oxidation, or, given the proper compound or mother substance in the absence of the specific oxidase, there is no oxidation. Hence, oxidation in the animal body is not the result of simple combustion, but, on the contrary, it consists of a series of orderly chemical processes, each one of which is presided over by an intracellular enzyme, specific in its nature, in that it is capable of acting only upon substances having a certain definite constitution, and leading invariably to a certain definite result. ”

“ Simplicity in diet, with or without complete abstinence from meat, is often resorted to as a means of relief from bodily ailments, and such cases sometimes afford striking illustrations of the adequacy and benefits of a relatively low intake of food. Cases of this sort, perhaps, are more frequently observed among elderly people, where the daily requirements are not so great as with younger and more active persons, but they offer evidence in support of our main thesis that dietary habits are no guarantee of bodily requirements. ”

“ Obviously, small numbers of tissue cells are constantly dying, their proteid matter passing into solution, where it likewise undergoes metabolism. In other words, according to Voit, the great bulk of the proteid undergoing katabolism is the circulating proteid, derived more or less directly from the food, and which at no time has been a part of the tissue framework; while a smaller, but more constant amount, represents the breaking down of tissue cells. This conception of proteid metabolism is akin to our conception of morphological and physiological destruction. ”

“ I do not believe that radical changes in diet, whether they involve increase or decrease in total quantities, or in specific elements of the diet, can be made suddenly without danger of some disturbance of the gastro-intestinal tract or other parts of the economy, either in dog or man. It is reasonable to believe also that a high proteid feeder, like a dog, with his more limited dietary, will be far more sensitive to great changes than omnivorous man with his wider range of foodstuffs. ”

“ 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. ”

“ 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. ”

“ We must be ever mindful of the fact, so many times expressed, that proteid does not undergo complete oxidation in the body to simple gaseous products like the non-nitrogenous foods, but that there is left behind a residue of non-combustible matter—solid oxidation products—which are not so easily disposed of. In the forceful language of another, “The combustion of proteid within the organism yields a solid ash which must be raked down by the liver and thrown out by the kidneys. Now when this task gets to be over-laborious, the laborers are likely to go on strike. ”

“ We may venture the opinion, however, for reasons to be made clear shortly, that the change in diet was in a measure at least responsible for the increased efficiency. As the writer has already expressed it, there must be enough food to make good the daily waste of tissue, enough food to furnish the energy of muscular contraction, but any surplus over and above what is necessary to supply these needs is not only a waste, but may prove an incubus, retarding the smooth working of the machinery and detracting from the power of the organism to do its best work. ”

“ Undue accumulation of fat is not only a mechanical obstacle to the proper activity of the body as a whole, but it interferes with the freedom of movement of such muscular organs as the heart and stomach, thereby interposing obstacles to the normal action of these structures. Further, whenever undue fat formation is going on in the body, there is the ever present danger that the lifeless fat may replace the living protoplasm of the tissue cells and so give rise to a condition known as “fatty degeneration.” ”

“ The standards which have been adopted more or less generally throughout the civilized world, based primarily on the assumption that man instinctively and independently selects a diet that is best adapted to his individual needs, are open to grave suspicion. The view that the average food consumption of large numbers of individuals and communities must represent the true nutritive requirements of the people is equally untenable. ”

“ I fancy that even the most vigorous and hardy man, if confined for six consecutive months in a room just large enough to furnish requisite air-space and to permit of extending his body at full length, would find himself at the end of such a period in a condition far from healthful, even though there were perfect freedom of choice in diet. ”

“ As has been pointed out, gastric digestion is primarily a process for the conversion of proteid food into soluble products. It would be a mistake, however, to assume that the digestion of proteid foods is complete in the stomach. Stomach digestion is to be considered more as a preliminary step, paving the way for further changes to be carried forward by the combined action of intestinal and pancreatic juice in the small intestine. The importance of gastric digestion is frequently overrated. It is unquestionably an important process, but not absolutely essential for the maintenance of life. ”