Physiological economy in nutrition, with special reference to the minimal proteid requirement of the healthy man / an experimental study

by R. H. Chittenden

These figures are interesting in many ways. First, they make clear that on the diet prescribed, these men were manufacturing or excreting about the same amount of uric acid per kilo of body-weight as the men of the two preceding groups, living more or less with free choice of food. In other words, all these men, with one and possibly two exceptions, were practically throwing out only uric acid of endogenous origin, i. e., that which came from the breaking down of the man’s own tissue cells. Second, it is to be noted that the ratio of uric acid to nitrogen in the men of this group varies only within narrow limits.

It is very evident from these figures, reinforced by those of the previous groups, that we can diminish greatly the output of uric acid by simply restricting the extent of proteid katabolism, through reduction in the amount of proteid food. Further, we now know that this general lowering of proteid metabolism can be accomplished not only without danger to the body, but with a distinct betterment of the physical condition.

Just here I should like to emphasize one point that appears to me of primary importance in any consideration of the influence of diet in gouty affections, and in so doing I merely echo a statement made by Sir Dyce Duckworth[53], viz., “that the subject of gout, either by inheritance or acquirement, is so far peculiar in his constitution that he reacts differently to various agencies, such as climate, food, etc., from persons not so disposed.” In this connection, let me refer again to the foregoing table of results obtained with the soldier detachment, remembering that these thirteen men were living under exactly the same conditions and consuming the same kind of food each day, and in essentially the same amounts. Yet notice the striking variation in the output of uric acid by one of these men (Sliney),—a variation which shows itself especially when the uric acid is calculated per kilo of body-weight. How can this variation be accounted for except on the assumption that there may be personal idiosyncrasies, personal coefficients of nutrition, natural or acquired, that modify to some extent the production of uric acid, the oxidation of uric acid, or the elimination of uric acid from the body?

Lastly, in advocating the possible systemic value of a lowered proteid metabolism as of value in the prevention of gout, and of other disorders which have their origin in perverted nutrition, I am inclined to emphasize the desirability of using common-sense in the application of dietetic rules, remembering that man is an omnivorous animal, and that Nature evidently never intended him to subsist solely on a “cereal diet,” or on any specific form of food to the exclusion of all others. 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. 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.

V. ECONOMIC AND SOCIOLOGICAL IMPORTANCE OF THE RESULTS.

The importance of the foregoing results from an economic and sociological standpoint is perhaps worthy of a brief consideration. We have learned that a much smaller amount of albuminous or proteid food than is ordinarily consumed will suffice for the daily needs of the body. It remains to be seen whether this fact will gain the popular recognition it would seem to deserve. Ignoring for the time the matter of physiological economy and its possible bearing upon health and strength, it is a fair question to ask why should people indulge in such wasteful extravagance in the matter of diet when there is no real physiological need for it? Why not accustom the body to a smaller consumption of food, thereby saving for other purposes the expenditure which this excess of food involves?

The question of the daily diet is one of the most important for the family of small means, and there is no reason why the family treasury should be so heavily drained for this imaginary need. Simplicity of living might well be given more careful consideration, and now that we have convincing proof of much smaller dietetic requirements on the part of the body, it might be well to consider the practical application these results naturally suggest. It is obvious from our data, that it is quite safe to diminish by one-half the amount of albuminous or proteid food ordinarily consumed, and this without any apparent detriment to health, and with even gain to the economy. The ordinary forms of proteid food are, as a rule, the most costly of dietetic articles, and since this restriction of albuminous food calls for no great increase in the amount of non-nitrogenous food, it is quite apparent that a great saving in the daily expenditure can be accomplished.

Obviously, however, there must be a decided change in the attitude of the public on this question before any great improvement can be hoped for. Habit and sentiment play such a part in our lives that it is too much to expect any sudden change of custom. By a proper system of education commenced early in life it may, however, be possible to establish new standards, which in time may prevail and eventually lead to more enlightened methods of living, whereby there will be less drain upon the resources of the people. With habits firmly fixed and palates calling for new sensations, reinforced by the prevalent opinion that by hearty eating lies the road to health and strength, it is easy to foresee difficulty in the advance of new doctrines along the lines indicated. The pleasure of eating is not to be minimized. The palate serves as the gateway through which food passes, and its sensitiveness and power of appreciation are not to be despised.

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. Neither is there implied any cessation of that kindly hospitality that delights in the ‘breaking of bread’ with one’s friends. With enlightened methods of living, on the other hand, will come a truer appreciation of the dignity of the body, and a lessened desire to manifest one’s feelings of hospitality by a lavish intemperance that is as unphysiological as it is wasteful.