Relation Between Serum Osteocalcin Levels and Body Composition in Obese Children

Overweight and obesity may contribute to bone fractures in children; however, the mechanism involved is not clear. In this study, we assessed the relation between serum osteocalcin levels and body composition in obese children. A total of 79 children (ages 7-12 years) were recruited. Serum osteocalcin levels were negatively correlated with fat percentage and visceral fat area (r=-0.24 and r=-0.46, respectively, P<0.05); however, no statistically significant association was found between obesity degree and serum osteocalcin levels (r=-0.29, P=0.052). Serum osteocalcin levels were positively correlated with lean body mass, fat-free mass, and fat-free mass index (r=0.24, 0.23, and 0.31, respectively; P<0.05). In addition, serum osteocalcin levels were significantly lower in severely obese (44.46 +/- 9.73 g/mL) and moderately obese (48.72 +/- 10.82 g/mL) children than in mildly obese (55.43 +/- 12.4 g/mL) and overweight (54.36 +/- 11.96 g/mL) children (P=0.02). These findings indicate that body composition is related to serum osteocalcin levels in overweight and obese children.