Unexpectedly low levels of energy expenditure in healthy women.

A new method for measuring total energy expenditure (TEE) with stable isotopically labelled water (2H218O) was used to measure average daily energy expenditure over 14-21 day periods in 12 healthy women following their normal activity patterns. TEE expressed as a multiple of basal metabolic rate (TEE/BMR) averaged only 1 X 38 +/- 0 X 04. This result is at variance with the widely held assumption that minimum maintenance requirements are 1 X 5 times BMR.