METABOLISM. 495 



|>arison with the ingesta, having regard to the C resulting from proteid 

 destroyed, shows that the body has lost 12.5 g. of its proteid but has 

 stored up 24.2 g. fat, containing 12.2 + 6.5 g. C." (Tigerstedt.) 



Fasting. 



After the first day of fasting hunger is felt, but it shortly vanishes. 

 Water is not very necessary, and man in fasting gives out more water 

 than he takes in. The pulse decreases, the temperature of the body 

 stands at normal until the last few days before death by starvation. 

 The weight of the body gradually lessens. During the first day of the 

 fast the glycogen disappears. In man with an abundant supply of fats, 

 the destruction of proteid gradually declines day by day. In animals 

 scantily fed after a temporary fall of proteid metabolism there ensues 

 a rise of metabolic changes of proteid. At the end of a fast when 

 food is given the body lays down proteid and fat in large quantities. 

 In fasting the body lives upon its own substance. 



Benedict has recently made a thorough study of the effect of 

 starvation on man. The daily loss of weight was from 44 grams to 

 1.7 kilograms. The body-temperature in general remained practically 

 constant during fasting, with a smaller amplitude of the curve than 

 usually is the case with man consuming food even under like condi- 

 tions of muscular activity. In the thirty days of a fast by Succi the 

 temperature was normal. The temperature only falls a few days before 

 death. The pulse-rate as the fast progressed showed a distinct tend- 

 ency to fall. The blood examination showed (1) a progressive 

 average fall in the number of erythrocytes ; (2) a corresponding 

 diminution in the percentage of haemoglobin; (3) a relative progres- 

 sive fall in the percentage of leucocytes in the prolonged fast. But 

 there was no remarkable effect of fasting on the relative percentage of 

 the various types of leucocytes. Tests of strength showed a noticeable 

 falling off when determined by the dynamometer. The nitrogen out- 

 put varied considerably from 5.8 grams on the first day of one 

 experiment to 15. grams on the third day of another experiment. 

 The output of nitrogen was rarely below 10.5 grams per day. Of 

 special significance is the fact that the nitrogen excretion on the 

 second day was on the whole much greater than on the first. Of 

 great significance is the fact that while the quantities of preformed 

 creatinin increased as the fast progressed, the total creatinin 

 remained singularly constant. From the first two days the uniformity 

 the carbon elimination was striking; as the fast progressed there 



a rather persistent decrease in the output of carbon dioxide. 



