THE TOTAL EXCHANGES OF THE BODY 619 



By means of one or more of these methods we may arrive at a correct 

 idea of the total income and output of an individual for periods of many 

 days. The following details by Tigerstedt may serve as an example of the 

 results obtained in such an experiment. The experiment lasted two days. 

 The subject was a man of twenty-six years of age, weighing about 65 kilos, 

 who had previously taken no food for five days. The following Tables 

 represent his material income and output. 



TOTAL INCOME 



TOTAL OUTPUT 



As we should expect in a man who had fasted five days, this balance-sheet 

 shows a marked retention of the food taken in, i.e. a marked excess of income 

 over output. Thus of the nitrogen ingested, 13 grm., which is equivalent 

 to 81-3 grm. of protein, was retained ; of the carbon, 302 grm. was retained. 

 Of this 302 grm., 42-7 grm. would be contained in the 81-3 grm. of protein, 

 so that the rest of the carbon, namely, 259-6 grm., was probably laid down 

 in the form of fat. This would correspond to 339 grm. of fat. Of the salts 

 contained in the ash of the food, 25 grm. were retained in the body. The 

 carbon and nitrogen reappearing in the excreta serve as an index of the 

 amount of metabolism of the food-stuffs which had occurred during the 

 two days. In order to supply the energy requirements of the body during 

 the time of the experiment, 498 grm. of carbohydrate, 59 grm. of alcohol, 



