PHYSIOLOGY : BENEDICT AND ROTH 
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well as measurements of the body surface, strength tests, and extensive psycho- 
physiological examinations of the neuro-muscular processes. The effects of 
the prolonged reduction in diet on these various functions were striking. 
Those dealing primarily with basal metabolism may be summed up as follows: 
1. A gradual reduction in weight to a point 12% below the initial weight 
took place during a period of from three to ten weeks, with low calories and a 
moderate amount of protein in the food intake. The normal demand of the 
men prior to the dietetic alteration ranged from 3200 to 3600 net calories. 
One squad of 12 men subsisted for three weeks on 1400 net calories without 
special disturbance. 
2. After the loss in weight of 12% had been reached, the net calories re- 
quired to maintain this weight averaged about 2300, or approximately one- 
third less than the original amount required. 
3. At the end of the reduction in weight, the actual heat output during the 
hours of sleep, as computed by indirect calorimetry, was approximately one- 
fourth less than normal, thus giving a rough confirmation of the lowered 
number of calories found by actual measurement of the food intake. That 
there was no seasonal variation in metabolism was shown by the constancy 
in the metabolic level of the control squad. 
4. The heat output by indirect calorimetry per kilogram of body weight 
and per square meter of body surface was essentially 18% lower than at the 
beginning of the study. 
5. The analyses of food, feces, and urine were sufficiently complete to per- 
mit a nitrogen balance to be made and it was found that throughout the 
period of loss in weight and for some time subsequent thereto, there was a 
marked loss of nitrogen to the body. In round numbers these men each lost 
approximately 150 grams of nitrogen. There is an intimate relationship 
between this ' surplus nitrogen' and the metabolic level. Removing what we 
may designate as 'surplus nitrogen,' we believe distinctly lowers the stimulus 
to cellular activity. 
6. The nitrogen output per day at the maintenance diet of 2300 net calories 
was about 9 grams. A control group of 12 men, living substantially the same 
life and eating in the same dining room, but with unrestricted diet, showed a 
nitrogen output of 16 to 17 grams per day. 
7. The pulse rate was astonishingly lowered. Many of the men showed 
morning pulse rates as low as 33 and daily counts of 32, 31, and 30 were 
obtained; at least one subject gave six definite counts on one morning of 29. 
8. The blood pressure, both systolic and diastolic, was distinctly lowered. 
9. The skin temperature, as measured on the surface of the hands and fore- 
head, was, with some subjects, considerably lower than normal. With most 
of the men normal temperatures prevailed. 
10. The rectal temperature was practically normal. 
The general picture that the men presented at the end of the test or at their 
minimum weight was one of noticeable emaciation, particularly in the face, 
