OBSERVATIONS ON WATER METABOLISM IN THE DESERT

Abstract

Water intakes and outputs were measured in 7 human subjects during 4 to 32 days, each at Boulder City, Nevada. Max. temps. were usually 35[degree] C (up to 43[degree] C), the mean humidity was 12%. Daily outputs by evaporation increased by 8-fold or more as compared with those in winter; outputs by urine were constant or decreased. In exercise, rates of evap. up to 1600 cc. per hr. were regularly found, and urine rates down to 10 cc. per hr. Daily turnovers of water were 10 to 30 times the daily variation of body wt. Daily intakes of water increased 3 to 6-fold. Ingestions lagged behind outputs during exercise and deficits were largely made up at meals. The rates of ingestion of water in man were slow in comparison with a donkey, which restored its whole deficit of water within a few mins. of drinking.