Body water distribution in highlanders versus lowlanders.

Acute exposure to high altitude produces characteristic changes in body water distribution from which acclimatized individuals seem to be spared. However, it has been suggested that body water distribution may be different in highlanders (HL) as compared to lowlanders (LL). We studied the distribution of total body water (TBW) between extracellular water (ECW) and intracellular water (ICW) in a group of 20 HL (3200 m above sea level) versus one of 20 LL (900 m above sea level). Subjects were matched for ethnic group (Kirghiz), sex (male), weight (Wt), height and body mass index. TBW:Wt and ECW:TBW were not different in HL as compared to LL (mean +/- SD, 58.5 +/- 5.0% versus 56.0 +/- 4.2% and 40.5 +/- 4.2% versus 40.7 +/- 2.2%; p = n.s. for both). This study does not support the hypothesis that body water distribution is different in HL as compared to LL.