GENERAL ASPECTS OF FASTING^ 



PAUL E. HOWE 

 (Department of Physiological Chemistry, University of Illinois, Urbana, III.) 



Fasting (starvation or inanition) is a State in which the dietary 

 elements are withheld, either wholly or in part, so that the organism 

 is compelled to draw upon its own resources to maintain its exist- 

 ence. In discussing this subject it is my purpose to make a rather 

 general survey of the changes which take place as the result of fast- 

 ing; to show briefly how such results have been used to elucidate 

 other scientific problems; and, also, to touch upon the therapeutic 

 value of fasting, with relation to man. 



A distinction is made between physiological and experimental 

 fasting. The first form is illustrated by the hibernation of mam- 

 malia (hedge hog and bear), and cold blooded animals (frog), by 

 the normal condition of the salmon during the spawning season and 

 by the period of metamorphosis of the insects, these being natural 

 phenomena for which the organism has made suitable preparation. 

 In experimental fasting the animal is forced to live without sus- 

 tenance, of one kind or another. Under this last State we may con- 

 sider pathological fasting as a special case in which the organism is 

 forced to fast as a result of impairment of some organ or of a gen- 

 eral diseased condition. These forms of inanition present certain 

 differences as evidenced in the effect upon the organism; yet it is 

 quite probable that they are chiefly phylogenetic and we can conceive 

 that any of the animals which do not experience these periodical 

 physiological fasts might do so under the proper adverse circum- 

 stances. 



In our discussion we will consider only the phenomena which 

 take place as the result of experimental fasting. Here, too, we must 

 distinguish between a number of forms of fast; such as the com- 



^ A lecture delivered at the College of Physicians and Surgeons, New York, 

 May I, 1912, under the auspices of the Columbia University Biochemical Asso- 

 ciation. 



90 



