American Journal of Clinical Nutrition, Vol 58, 137-140, Copyright © 1993 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Variability of fecal energy content measured in healthy women

JL Murphy, SA Wootton and AA Jackson
Department of Human Nutrition, University of Southampton, UK.

The variability of daily stool energy losses was examined in six healthy adult women over a complete menstrual cycle. On average, stool energy was 0.74 +/- 0.15 kJ/d (mean +/- SD) for the group. For a given individual, daily stool energy varied up to twofold. The variability for rolling averages of daily fecal energy losses over 3-, 5-, and 7-d periods showed no significant differences between collection periods of 3 and 5 d and 5 and 7 d. There was a close linear relationship between the energy content of the stool and either the wet or dry weight of stool (range 17-460 g wet wt). In metabolic studies of healthy women representative values for daily losses of energy in stool can be obtained from a 3-d collection. The energy content of wet stool was approximately 7 kJ/g. Under field conditions, weighing the stool provides a simple, useful method of assessing fecal energy losses.