Effect of Age on the Body's Tolerance 



141 



The same principles have been used in estimating the upper 

 and lower limits of body tolerance for water and certain 

 electrolytes for normal individuals of various ages, depicted 

 in Fig. 2. The upper limits shown in this figure are of necessity 

 approximate, being based on the relatively few data available 

 in the literature and the files of our metabolic unit (Talbot 

 et ah, 1952; Talbot, Crawford and Butler, 1953; Talbot et ah. 



HEIGHT OF 

 T WAVES 2 



IN LEAD IE 

 mm. 



INPUT 



a 60 



OUTPUT 

 mEq / m^/ day 



Fig. 1. Demonstration of physiological maximum tolerance for 



potassium in a patient with impaired kidneys. (From Talbot 



et al., 1956). 



1955, 1956; Talbot, Richie and Crawford, 1958). In all 

 instances, they are intended to represent levels which can be 

 attained by healthy individuals within a day or so and not the 

 uttermost levels which can be attained after extensive prior 

 conditioning. The lower limits include normal growth re- 

 quirements for infants and children, a factor of relatively 

 small size after the first few months of life. It can be seen that 

 with the exception of young infants, individuals normally 



