CGO JOHN R. MUELIN 



From the Nutrition Laboratory at Boston are available a few scat- 

 tered data on the basal metabolism of old people. For example, Benedict 

 (/) in a discussion of the factors affecting basal metabolism includes in 

 one of his tables one man 63 and one woman 74 years of age and notes 

 that a person "of advanced years has a still lower metabolism than the 

 person in middle life." 



Magnus-Levy observes in explanation of the low metabolism of old age 

 that "the cells of the body lose their thermodynamic powers with old 

 age" and cites the older observations of Andral and Gavarret, Son- 

 den and Tigerstedt and his own work with Falk in support of 

 the view that an old man utilizes less food, not only because his output 

 of work is less, but also because his cells generate less heat during rest. 

 Whatever special causes may underlie the onset of senility physiological 

 eld age can only be said to exist when the involution of the various organs 

 takes place gradually and at a proportional rate. In such changes is found 

 sufficient cause for the decreasing metabolism. How low the hour-glass 

 must run before the processes of oxidation must cease or what level 

 of heat production marks the ultra-minimum for the support of respira- 

 tion and circulation has not yet been disclosed. "And his days were 

 ended and he died, for he was old and weary of life." 



