Abstract
In this study, serum leptin concentrations were examined in Japanese adolescents. Serum leptin concentrations were measured by radioimmunoassay, and height, weight and percentage body fat were also measured in healthy non-obese subjects (junior high school age: n=352, high school age: n=446). The mean serum leptin concentration differed significantly by both sex and age. The 95% confidence intervals were 1.0-7.8 ng/mL for boys and 2.1-15.9 ng/mL for girls at junior high school, and 0.8-5.0 ng/mL and 3.0-16.4 ng/mL for boys and girls, respectively, at high school. There was a significant positive correlation between serum leptin concentration and percentage body fat, although the regression line for this relationship differed significantly between boys and girls. The regression line did not differ by school year, and there was no difference between post-menarche and pre-menarche in girls. Therefore, these results suggest that serum leptin concentrations in adolescents may be estimated by measurement of body fat percentage, regardless of age and the presence or absence of menarche.
