COMPLEXITY OF OUR DIETARY REQUIREMENTS 51 



embraces any of the dietary fads and "systems" which are so prevalent 

 in this uninformed and loquacious period of our social evolution. The 

 average man or woman hesitates to pronounce an opinion on the motive 

 machinery of steamships or aeroplanes or on the fuel-requirements of 

 a Diesel engine, but regarding that infinitely more complex engine, a 

 human being, the average individual deems himself fully informed and 

 all that is required to make numerous converts to any dietetic fad is a 

 considerable degree of self-assurance. 



So complex are the requirements of the animal economy; so little 

 do we know the parts that these several requirements play and their 

 delicate adjustments to one another, that we are totally unable at this 

 stage of our knowledge to enumerate the constituents of any restricted 

 dietary which shall certainly and for prolonged periods of time, convey 

 to the subject all that he requires for the orderly functioning of his 

 body. In medical practice it is, of course, necessary to occasionally 

 prescribe a limited and specified diet for a definite period in order to 

 combat certain conditions or maladies, but to do so for lengthy periods 

 of time, especially for growing infants and children, is to simply assume 

 a knowledge which we do not possess. The problem of the dietary 

 requirements, as we have seen, is complex enough when we consider 

 only the inorganic foodstuffs; but when we add to these the organic 

 requirements of the body the complexity of the problem of nutrition 

 is multiplied a hundredfold, and we are as yet hopelessly in the dark 

 respecting the source and function of a multitude of constituents of the 

 body and of the degree to which they may be essential. Our knowl- 

 edge in this field is rapidly extending, perhaps more rapidly at present 

 than in any other field of biochemistry, but even at the present rate 

 of accession of knowledge, the complete knowledge essential for enumer- 

 ation in detail of all the dietary requisites of a human being is very 

 far distant indeed. 



The knowledge that we do possess, however, enables us in certain 

 particular instances, as, for example, in the Weir Mitchell treatment 

 of certain nervous disorders, or the Allen treatment of diabetes, to 

 accomplish very decisive therapeutic results by restricted dietaries 

 prescribed for limited periods, in conjunction with hygienic measures 

 and adequate biochemical and clinical observation and control. The 

 very success of such measures in any particular instance carries with 

 it the danger of converting an ignorant patient into a fanatical diet- 

 faddist who, upon recovery of health, proceeds to convert, first his 

 acquaintances and then, if he has the opportunity, a wider public, to the 

 health doctrine which he has evolved out of the temporary measures 

 of the physician. This is no doubt the origin of many of the dietary 

 and hygienic eccentricities to which certain genuine or imaginary 

 invalids devote themselves. No small part of this perverted activity 

 could probably be stifled at its birth, if the physician who is prescribing 

 dietary or hygienic measures were to make a practise of explaining as 

 thoroughly and simply as he is able, to the patient and his immediate 



