STATE OF NUTRITION. 203 



tant in making as comprehensive a study as practicable of the welfare 

 and general physical condition of man to include observations of possi- 

 ble influence upon reproductive processes.^ 



Nature has thus provided for material changes in the nutritional level, 

 and particularly for possibilities of long drafts upon body-material 

 either with deficient nutrition or during complete fasting. But there is 

 likewise (among animals, at least) a pronounced rise in weight on the 

 return to normal feeding after the prolonged drafts. For instance, 

 immediately after hibernation, the bears begin to eat voraciously 

 and accumulate a storage of fat preliminary to the next season's 

 hibernation. The seals proceed to their feeding-grounds and return 

 the following year in prime condition. This recovery of weight after 

 hibernation or after low nutritional level must be considered likewise 

 in this study with men. Fortunately, our observations throw some 

 light upon the rapidity of return to body-weight after a prolonged 

 period of reduced diet and contribute materially to this question. 



It would appear that with humans those individuals who are 

 accustomed to frequent or relatively frequent fasting have a distinct 

 tendency to increase in weight. The excessive eating following re- 

 stricted diet has been noted in a great many places. One of us, on a 

 visit to Petrograd, was informed by Professor Pawlow that the sale of 

 the artificial gastric juice prepared in the Laboratory of Experimental 

 Medicine was relied upon in large part to sustain the experimental 

 laboratory. Prior to the war, Russian fast days were very frequent, 

 and Professor Pawlow remarked that if one plotted the Russian fast 

 days and also the sale of artificial gastric juice, it could be seen that 

 peaks in the curve of the sale of gastric juice invariably followed a few 

 days after each fast day. In other words, after fasting the Russians 

 ate voraciously ; this produced digestive disturbance and they would then 

 purchase the gastric juice for therapeutic purposes. Our own experi- 

 ence with a number of the subjects of the low-diet research bears out 

 in general these experiences, ^. e., that following a period of restricted 

 diet there is a distinct tendency toward overeating and like-wise 

 toward a rapid and frequently a sustained increase in body-weight. 



The experiences of athletes likewise tend to show that after a period 

 of athletic training with restriction in diet and severe muscular exercise 

 there is a proneness to take on considerable weight. Nevertheless 

 these conditions have been so commonly overlooked by physiologists 

 that, so far as we are aware, no specific studies of metabolism have 

 been jnade for these apparent variations in nutritional level with man, 

 or such simple indices of metabolism as pulse-rate and blood pressure 

 recorded under these conditions. In the following chapters we purpose 

 discussing the effects of a prolonged reduced diet and its accompanying 



^ See page 638; also Miles, Journ. Nervous and Mental Disease, 1919, 49, p. 208. 



