CHAPTER XV 



THE EFFECT OF DIET ON THE DISSOCIATION CURVE OF BLOOD 



IN company with my colleagues I have made efforts, in several 

 directions, to move the dissociation curve in individuals away from 

 its mesectic position. Naturally such attempts would take the line 

 of subjecting the patients to some form of treatment which is known 

 to alter the acid radicles in the blood either in quantity or in kind. 

 The first of these attempts which I will chronicle was made by 

 Higgins and myself. It is perhaps the simplest, and as it illustrates 

 a good many of the principles involved in the more complicated 

 researches which follow, I will describe it in some detail. My col- 

 league on this occasion was a specialist not only in gas analysis, 

 but in the physiology of dietaries, coming as he did on a visit to 

 Cambridge from the Nutrition Laboratory at Boston, U.S.A., presided 

 over by Professor Benedict. Moreover, since Higgins visited this 

 country he has continued the work at Boston. The motif of the 

 research was as follows : all carbohydrate was strictly eliminated 

 from the diet, and this of course led to an acidosis the most obvious 

 evidence of which was the appearance of /3-oxybutyric acid, diacetic 

 acid, &c. in the urine. Here let me explain my use of the word 

 acidosis in reference to the blood. In the following pages it will 

 signify the appearance of acids (exclusive of C0 2 ), abnormal in kind 

 or perhaps only in quantity in the blood or even a decrease in the 

 bases present. By acidosis then I mean an increase of acid relative 

 to basic radicles in the blood, C0 2 not being considered. But by the 

 term acidosis I will signify nothing concerning the final "reaction" of 

 the blood which is largely regulated by the amount of C0 2 present. 

 The question for decision was, Would the dissociation curve depart 

 from its mesectic position owing to these bodies being thrust into the 

 blood by the tissues, i.e. owing to the acidosis? And here we are at 

 once face to face with the distinction which we drew at the close of 



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