Abstract
The primary objective of this study was to determine annual changes in body fat of young Japanese children. We also assessed annual changes in body fat distribution [subcutaneous fat mass (SFM) and internal fat mass (IFM)]. Measurements of body composition by bioelectrical impedance were made in 72 boys and 88 girls, all apparently healthy, aged 3-6 years. Determinations of impedance were made using a four-terminal impedance analyzer (TP-95K, Toyo Physical, Inc., Fukuoka, Japan). LBM was calculated using the equations of Kushner et al. (1992) and Goran et al. (1993). SFM was calculated using a modification of the equation derived by Skerjl et al. (1953). IFM was calculated as the difference between total body fat mass (TBFM) and SFM. The annual increments in skinfold thickness increased with age for boys, but not for girls Although the annual increments in SFM did not differ significantly with age, the annual increments in TBFM,IFM and %Fat increased with age for boys and girls: %Fat values 15.9 - 19.0% for boys aged 3 - 6 yr, and 19.8 - 21.2% for girls aged 3 - 6 yr. When body mass increased by 1 kg, TBFM increased by 0.54 kg for boys and 0.39 kg for girls. We conclude that the annual increments in TBFM show significant age - related changes and sex differences in young Japanese children aged 3 - 6 yr.
