CONCERNING LOW PROTEIN DIETARIES 147 



How are these contradictory results to be explained ? It has 

 been suggested that, while Fletcher oxidized his own tissues to 

 obtain the extra energy required, owing to the amount of carbo- 

 hydrates in his diet, retention of water took place, so that the 

 body weight remained the same. This may be the true ex- 

 planation, but it seems a strange coincidence that the weight 

 of water retained should exactly balance the loss to the body 

 through the disintegration and oxidation of its tissues. What 

 appears a far more rational explanation would be that, owing to 

 faulty methods, the caloric value of Fletcher's dietary during the 

 six days was estimated at too low a figure. 



This explanation is borne out by a consideration of the ex- 

 perimental work on Chittenden's second group of subjects the 

 members of the Hospital Corps. It will be readily recognized 

 that a retention of water maintaining the body weight might 

 act temporarily, but that it could not go on indefinitely. 



What are the facts ? 



Benedict and Carpenter* have shown, as a result of experiments 

 in the respiration calorimeter on fifty-five men, with an average 

 body weight of 64-5 kilos, awake and sitting quietly in a chair, 

 that the average heat production was 97 calories per hour. 



Calories per Hour. 



With seventeen men asleep, the heat production was . . 71 

 Man at rest, standing, the heat production was . . . . 114 

 Man at severe muscular exercise, the heat production was 653 



Chittenden's soldier group led quite active lives, rising at 

 6.45 a.m., occupied with various duties all day, including two 

 hours' activity in a gymnasium in addition to regular drills, 

 walking, instruction in nursing duties, assisting in laboratory 

 work, etc. 



According to Chittenden's figures, the average heat value of 

 the diet was 



Calories. 



From October to the middle of January 2,078 



From middle of January to early in March . . . . 2,500 

 From early in March to early in April . . . . . . 2,840 



The average caloric value of the dietaries for the six months 

 of observation works out at a little over 2,300 daily. This 

 amount, according to accurate determinations based on exact 

 scientific experimental methods, would not be nearly sufficient to 



* Benedict and Carpenter, " Metabolism and Energy Transformations of 

 Healthy Man during Rest," 1910. 



