THE FOOD REQUIREMENT OF THE SICK 35 



According to a diagram proposed by Magnus-Levy ^ the total metabolism 

 of an individual may be considered to be composed of three factors : 



1. The entire metabolism in rest and with an empty stomach. 



2. The metabolism which is necessary to sustain the work (glandular and 

 intestinal) that results in the assimilation of food introduced. 



3. The metabolism which is necessary for useful or useless movements of 

 the body. 



Metabolism thus estimated amounts : 



For 1 to 1,600 calories. 



For 3 to 240 " 



For 3 to 860 " 



Total 2,700 



In fact it is unlikely that an obese person requires less energy than a 

 healthy person for the maintenance of his vital functions, for normal activity 

 of the heart and respiration, for the rest metabolism of the glandular activity 

 and for the maintenance of body heat. v. Noorden mentioned the possibility 

 that for 3 he saves something, because the development of heat which accom- 

 panies physical exercise per kilogram of working protoplasm and per kilo- 

 gram-meter of physical exercise is less in him than in the average person, but 

 Magnus-Levy expressed his doubts of this. It was therefore particularly in- 

 teresting that Jaquet found the value for 3 diminished in his corpulent patient. 

 The increase of the products of combustion due to ingestion of nourishment 

 was decidedly less and of shorter duration in his three obese patients than 

 in normal persons. It was shown that during a period of digestion reckoned 

 as fourteen hours, the obese require 31.84 liters Oj less than a normal person 

 under similar circumstances. With this amount of 0^, 11 grams of fat can 

 be burned, and a daily saving of 11 grams of fat corresponds to an accumula- 

 tion of 4 kilograms of fat a year. Thus the analysis of respiratory metabolism 

 opens a path for the understanding of the pathogenesis of constitutional 

 obesity. 



Practical rules for the nutrition of the sick cannot be immediately deduced 

 from these clinical studies regarding the amount of respiratory metabolism in 

 the diseases which have been mentioned, valuable as they are for our knowl- 

 edge of disturbances of metabolism. 



The knowledge of Oj consumption and COj excretion, conveyed to us in 

 the clinical investigations which are almost exclusively carried out by Zuntz's 

 method, with simultaneous estimation of albumin metabolism (by N-estima- 

 tion in the urine) can give at most but approximate conclusions regarding 

 the part played by individual food substances in combustion. The respiratory 

 quotient gives us some information but the absolute value of the transference 

 of energy in a unit of time cannot be calculated from the " minute-values " 

 for Oj and COj, because, as was mentioned above (page 8), the same amounts 

 of carbonic acid and oxygen correspond to entirely different degrees of heat, 



1 Magnus-Levy, Zeitsohr. f. klin. Med., Bd. xxxiii, p. 299. 



