COMSUMPTION OF FOOD IN THE HEALTHY 5 



The more complete the technie, and the more ingenious the investi- 

 gation, the more certainly the results show that metabolism is determined 

 by the activities of the body (heat production and force). Then by excluding 

 all external factors which could increase metabolism, it is shown that the 

 " resting-energy " ^ of metabolism is equivalent in its potential value to the 

 amount of heat produced. This has unquestionably been proven by Rubner's 

 calorimetric investigations. 



In rest, the dissipation of heat is the only avenue for loss of force. Dis- 

 sipation of heat, however, is a function of the surface of the body. If it 

 determines the ratio of metabolism in rest, this metabolism must in turn be 

 dependent upon the surface of the body (law of the development of the sur- 

 face, Rubner). 



There can be no doubt that this biologic law also exists in pathology. 

 Where conspicuous differences in the amount of the resting-energy per kilo- 

 gram of body-weight exists, an attempt should be made to explain it by the 

 variation in the amount of 'surface before we accept the view that a special 

 protoplasm, characterized by a more active or sluggish metabolism, plays a 

 role (in nurslings, in obesity, etc.). 



^ Table I 

 ENERGY METABOLISM PER SQUARE METER OF BODY SURFACE' 



Atrophic child (cow's millt). , 

 Atrophic child (infant milk) 



Breast-fed child. 



Normal child (cow's milli). . 



Boy, thin 



B07, fat 



Man 



Man 



Man 



Man 



Man 



The metabolism which takes place normally in the body of a mammal when 

 in absolute rest, for the purpose of .maintaining life, is always the same, with- 

 out regard to the source whence it obtains the organic material to fulfil its 

 needs — whether from albumin, fat, or carbohydrates. 



For the maintenance of life the organic food products compensate accord- 

 ing to their specific energy of tension {law of isodynamics) . The amount of 

 energy which the individual food products contribute to the processes of 



1 German : Ruherverth. 



2 Buhner, Beitrage zur " Ernahrung im Knabenalter," Berlin, 1902, p. 62. 



3 Weight with clothing. 



* Calculated from the carbonic acid values. 



