112 H. Victor Parker, et al. 



From the uniform tendencies in these materials it seems 

 reasonable to conclude that the slight decrease in total body 

 water and in intracellular water related to body weight 

 reflects real alterations in the body composition with advanc- 

 ing age. With the decrease in the relative value for total 

 body water there is a relative increase in total body solids. 

 As the intracellular phase shows a relative decrease the 

 increase in total body solids must be assumed to be caused by 

 a relative increase in non-cellular solids, most probably body 

 fat. 



The alterations in the extracellular water related to body 

 weight are not quite uniform and the changes are small. It is 

 of interest that extracellular water expressed as per cent of 

 total body water in both sexes shows a rise from younger to 

 older subjects, in the males from 43 per cent to 50 per cent, in 

 the females from 47 per cent to 49 per cent. This tendency is 

 also seen in Shock's and in Olbrich and Woodford-Williams' 

 series and indicates an altered relationship between the 

 extracellular and intracellular water. 



In conclusion: the alterations in body composition in the 

 old age group as compared to younger adults were rather 

 small. A tendency to a relative decrease in total body water 

 and in intracellular water and a relative increase in total body 

 solids, most probably body fat, was found. The extracellular 

 water stayed essentially the same in values related to body 

 weight, but demonstrated a tendency to increase in per cent 

 of total body water. 



Acknowledgement 



We express our gratitude to Dr. Francis D. Moore, Moseley Professor 

 of Surgery, Harvard Medical School, and Surgeon-in-Chief, Peter Bent 

 Brigham Hospital, Boston, for permission to present data from his 

 laboratory. 



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Arons, W. L., Vanderlinde, R. J., and Solomon, A. K. (1954). J. 



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 Barlow, J. S., and Manery, J. F. (1954). J. cell. comp. Physiol., 43, 165. 

 Blainey, J. D., Cooke, W. T., Quinton, A., and Scott, W. C. (1954). 



Clin. Sci., 13, 165. 



