GENERAL METABOLISM. 



647 



From the values published by Atwater it is apparent that the diet 

 chosen by people of various callings is very different both as regards the 

 composition and calorific value. In order to be able to estimate the extent 

 to which the food chosen suffices to meet the requirements which are placed 

 upon the organism, it is necessary to make use of the average values 

 obtained by direct experiments upon metabolism. In order to establish 

 the minimum requirement of the human organism, the metabolism is 

 studied under conditions at which the muscles are as much at rest as possi- 

 ble. In twenty-four hours the requirement per kilogram of body-weight 

 has been found to amount to from 30 to 36 calories. The average man 

 may be assumed to weigh about 70 kilograms, and on this basis the mini- 

 mum requirement per twenty-four hours would be 2100 to 2520 calories. 

 This value does not hold for absolute rest, when the requirement is con- 

 siderably less. The resting organism is satisfied with considerably less 

 food, as has been shown by metabolism experiments with a woman in 

 hysterical coma. 1 The minimum requirement was then only 1680 calories. 

 It is impossible for the muscles to be in such a state of rest when the per- 

 son is awake. Now from the computed values for a person resting as 

 much as possible, we may pass judgment upon the values given in the 

 above tables. Unquestionably some of the above individuals were under- 

 fed. According to the wide experience of Voit, the daily diet of an adult 

 engaged during nine or ten hours in ordinary work should be about 2749 

 calories. 2 This amount may be distributed among the different nutrients 

 as follows: Protein 118 grams, fat 56.0 grams, carbohydrates 500 grams. 

 The more work there is to be done, the more calories are needed. Thus 

 Voit estimates that soldiers engaged in maneuvers require 135 grams 

 albumin, 80 grams fat, and 500 grams carbohydrates, amounting to 3018 

 calories. In time of war, however, the requirement he states to be 145 

 grams protein, 100 grams fat, and 500 grams carbohydrates, which is 

 equivalent to 3218 calories. Working women, on the other hand, require 

 but 2200 calories, which should be composed of 94 grams protein, 45 grams 

 fat, and 490 grams carbohydrates. 



1 Sonden and Tigerstedt: Skand. Arch. Physiol. 6, 1 (1895). J. E. Johansson, E. 

 Landgren, K. Sond&i and R. Tigerstedt: ibid. 7, 29 (1896). 



3 After subtracting the calories lost by insufficient utilization. This deduction is 

 not made in the case of the values given for the separate nutrients. 



