Changes in adipocyte cellularity in children ten to 18 years of age.

Adipocyte size and number, and total body fat were collected serially from boys and girls living in South-western Ohio. Sex-specific annual increments were computed across age for each of these variables. During adolescence, the boys had a near zero mean increment in total body fat, but the girls had a positive mean increment in total body fat. In both the boys and girls, there were negative mean increments in adipocyte size and positive mean increments in adipocyte number. Sex-specific age-to-age correlations are statistically significant for adipocyte number and total body fat but not for adipocyte size. These data indicate that increases in total body fat during adolescence may be due to increases in adipocyte number and that annual increments in adipocyte size may provide little information in regard to changes in total body fat.