Bioelectrical Impedance vs. Four-compartment Model to Assess Body Fat Change in Overweight Adults
Article first published online: 6 SEP 2012
2007 North American Association for the Study of Obesity (NAASO)
Volume 15, Issue 1, pages 85–92, January 2007
How to Cite
Chouinard, L. E., Schoeller, D. A., Watras, A. C., Clark, R. R., Close, R. N. and Buchholz, A. C. (2007), Bioelectrical Impedance vs. Four-compartment Model to Assess Body Fat Change in Overweight Adults. Obesity, 15: 85–92. doi: 10.1038/oby.2007.510
- Issue published online: 6 SEP 2012
- Article first published online: 6 SEP 2012
- Received for review March 09, 2006, Accepted in final from September 12, 2006
- body composition;
- conjugated linoleic acid
Objective: The Tanita TBF-305 body fat analyzer is marketed for home and clinical use and is based on the principles of leg-to-leg bioelectrical impedance analysis (BIA). Few studies have investigated the ability of leg-to-leg BIA to detect change in percentage fat mass (%FM) over time. Our objective was to determine the ability of leg-to-leg BIA vs. the four-compartment (4C) model to detect small changes in %FM in overweight adults.
Research Methods and Procedures: Thirty-eight overweight adults (BMI, 25.0 to 29.9 kg/m2; age, 18 to 44 years; 31 women) participated in a 6-month, randomized, double-blind, placebo-controlled study of a nutritional supplement. Body composition was measured at 0 and 6 months using the Tanita TBF-305 body fat analyzer [using equations derived by the manufacturer (%FMT-Man) and by Jebb et al. (%FMT-Jebb)] and the 4C model (%FM4C).
Results: Subjects in the experimental group lost 0.9%FM4C (p = 0.03), a loss that did not reach significance using leg-to-leg BIA (0.6%FMT-Man, p = 0.151; 0.6%FMT-Jebb, p = 0.144). We observed large standard deviations (SDs) in the mean difference in %FM between the 4C model and the TanitaManufacturer (2.5%) and TanitaJebb (2.2%). Ten subjects fell outside ±1 SD of the mean differences at 0 and 6 months; those individuals were younger and shorter than those within ±1 SD.
Discussion: Leg-to-leg BIA performed reasonably well in predicting decreases in %FM in this group of overweight adults but resulted in wide SDs vs. %FM4C in individuals. Cross-sectional determinations of %FM of overweight individuals using leg-to-leg BIA should be interpreted with caution.