 ANGPTL3 and ANGPTL8 are emerging molecules involving lipid metabolism. In previous in vivo study using mice, ANGPTL8 regulated the activation of ANGPTL3 which was known to inhibit lipoprotein lipase activity and stimulate lipolysis of adipose tissue. Besides, glypican 4 was identified as a novel adipokine modulating adipocyte differentiation. Thus, the investigators postulated that different serum concentrations of ANGPTL3, ANGPTL8 and glypican 4 might affect progression of obesity in children. The investigators measure these molecules in Korean children, and investigate the association between these molecules and development of obesity. 