PREVIOUS INVESTIGATIONS. 33 



nitrogen balance. All of the subjects, with the exception of two 

 women in the group, had lost not far from 8 to 10 per cent in body- 

 weight since the beginning of the war. The diet, which corresponded 

 to the Munich ration in March 1917, had an energy value of about 

 1,600 (gross) calories per day, with a nitrogen content of approximately 

 9.7 grams (or 60.5 grams of protein) and contained 210 grams of 

 carbohydrates. On this diet there was an average loss of nitrogen 

 for the whole group of about 2 grams per day and an average loss in 

 body-weight of 0.28 kilogram per day. 



Respiration experiments were also made by the Zuntz-Geppert 

 method with two subjects 23 and 26 years old, and of the same height 

 and weight, i. e., 174 centimeters and 56.1 kilograms. The basal 

 heat production per 24 hours found in these experiments was 1,338 

 calories and 1,456 calories, respectively, while on the basis of per 

 kilogram of body-weight it was 23.8 and 25.0 calories, respectively. 

 Jansen points out that these values are low as compared with Magnus- 

 Levy's values for normal subjects of like weight^ and refers to the 

 explanation of Loewy and Zuntz that this lowering in metabolism is 

 due to the loss in active cell substance. 



The basal metabolism of these subjects after a 3-day walking trip 

 was again measured 12 hours after the last meal and after work and 

 was found to be very greatly increased. The post-absorptive respira- 

 tory quotients for both subjects varied considerably, ^. e., from 1.29 

 to 0.78 and from 1.10 to 0.86, respectively, whereas in the previous 

 series of experiments the quotient had averaged about 0.87. The 

 oxygen consumption likewise varied considerably with one subject, 

 and the lung ventilation was greatly increased. Jansen concludes 

 that this amount of exercise, which would not be considered at all 

 strenuous with a well-nourished man, produced with these subjects 

 on restricted diet an extraordinary exhaustion and affected the respira- 

 tory exchange even after 12 hours of repose, this being shown by 

 abnormally high values for oxygen consumption and the respiratory- 

 quotient. Unfortunately the respiratory data, judged in the light 

 of our own observations, seem to be of uncertain value. Such astonish- 

 ing alterations in the respiratory quotient and, indeed, in the basal 

 oxygen consumption, are outside of our experience. It is to be hoped 

 that the data will be supplemented by publications from other Euro- 

 pean laboratories where metabolism studies on the influence of a 

 reduced diet have doubtless been made. 



SUMMARY OF PREVIOUS LITERATURE. 



In studying the results of previous investigations on undernutrition, 

 it is of the greatest importance to note that there is a marked difference 



1 Calculation by the Harris-Benedict multiple prediction formula (Harris and Benedict, Car- 

 negie Inst. Wash. Pub. No. 279, 1919) gives 1,553 and 1,533 calories per 24 hours, 

 respectively, x, c, 16 and 5.5 per cent above the found values. 



