Most measurements of the total body water in man using dilution techniques have been made using antipyrine or deuterium oxide (D2O) as tracers. In adult subjects, Schloerb and co-workers, using D2O, obtained mean values of 61.8% and 51.9% of the body weight in male and female subjects, respectively.1 Slightly lower values have been reported using antipyrine.2,3 Body-water percentage appears to decrease with advancing years, apparently due to increase of body fat.6 The earlier literature on body-water measurements by desiccation and other methods has been reviewed by Levitt and Gaudino7 and by Pace and associates.8
In children, Friis-Hansen and co-workers4 determined that body water constituted from 53% to 63% of body weight in "hospital normal" children over 6 months of age, regardless of sex. Higher values were obtained in young infants.
Apart from the patient studied by Pace 8 and the
JAMES JA, ROBERTSON JS. Estimation of Exchangeable Water and Potassium by Radioisotope Dilution in Children. AMA Am J Dis Child. 1957;93(3):217-222. doi:10.1001/archpedi.1957.02060040219001