274 



Scientific Proceedings (116). 



The very close agreement in total Ca and P between periods 

 in this experiment is accidental, the other experiments showing 

 a somewhat greater variation. It is seen that in the second 

 period, while the total P and Ca is the same as in period I, its 

 distribution between urine and feces is changed. In the normal 

 period, 57 per cent, of P and 28.7 per cent, of Ca are found in the 

 urine, while in the alkaline period, these figures are 44 per cent, 

 and 22 per cent, respectively. The acid period shows a reversal 

 of this change, more Ca and P appearing in the urine. 



Considering the fact that as high as 70 per cent, of the ash of 

 feces is made up of Ca and P it seems quite plausible that an 

 equilibrium condition should exist between the calcium phos- 

 phates in the intestine and the Ca and P of the blood and tissues 

 which is influenced by the relative amounts of acid and base being 

 metabolized. That Ca and P, with regard to absorption of re- 

 excretion in the intestine, play a role entirely different from the 

 other mineral elements is apparent from analyses of intestinal 

 contents at various stages of digestion and the feces. 2 



Fitz, Alsberg and Henderson assumed that the increased phos- 

 phate in the urine after acid administration came from the tissues. 

 This undoubtedly is true with extreme acidosis, but the data here 

 recorded seem to show that urinary Ca and P can be increased 

 at the expense of the fecal Ca and P, without loss to the body, if 

 the acidosis is mild. A moderate dose of NaHCC>3 may produce 

 the reverse effect, without storage of Ca or P, in the body. 



Besides the general biochemical significance which these data 

 have, their application to nutritional studies and such problems 

 as rickets should not be overlooked. The Ca and P excreted in the 

 feces may be considered not available to the tissues and since the 

 relative amount of acid and base in the diet influences the loss of 

 Ca and P in the feces, the same level of intake may have a dif- 

 ferent nutritional significance, depending on the acid base equili- 

 brium. The latter may be influenced not only by preponderance 

 of acid or base forming elements in the food, but also by metabolic 

 acidosis or alkalosis or possibly even by the intestinal bacterial 

 flora. 



2 For data see Schmidt and Strassburger, "Die Faces des Menschen," or Schreuer 

 in Oppenheimer's Haridbuch, Band III, 2. 



