MEASUREMENT OF FECAL CARBOHYDRATE IN HUMAN METABOLIC BALANCE STUDIES - CALCULATED VERSUS DETERMINED

Fecal carbohydrate in human metabolic balance studies is normally dete rmined using a calculation method where fecal energy (kcal) from prote in and fat is subtracted from total fecal energy, and divided by 4.1 k cal/g, the heat of combustion of carbohydrate. This method, however, h as not been validated. In this study fecal carbohydrate in 17 preschoo l children, consuming diets containing cassava, amaranth, maize, or a casein control;diet, was determined analytically as fiber and starch. A correlation coefficient of r=0.856 (P<0.001) was found when comparin g the two methods, thus, supporting the use of the calculation method. Mean calculated fecal carbohydrate slightly underestimated actual val ues in the cassava group (17.6 vs. 20.3 g/day) and slightly overestima ted values in the amaranth group (12.3 vs. 8.3 g/day), though this was not considered a significant problem.