Changes in serum interleukin-6 concentrations in obese children and adolescents during a weight reduction program

Abstract

To investigate the effect of short term energy restriction combined with physical activity on serum concentrations of Interleukin-6 (IL-6) in obese children and adolescents. Longitudinal intervention study of 3.8-5 MJ daily with exercise. Forty-nine white obese children and adolescents (31 girls, age 11.9+/-1.8 y; 18 boys, age 11.6+/-1.7 y). Indexes of obesity, IL-6, leptin, estradiol, systolic and diastolic blood pressure, heart rate at baseline and after 3 weeks. All determined parameters decreased significantly during the 3 week program (IL-6: 3.9+/-4.7 vs 2.0+/-2.2 pg/ml; P<0.05). Body mass index (BMI) fat mass, percentage fat mass (indexes of obesity), and leptin were not related to IL-6 before the program. In contrast, IL-6 concentrations correlated significantly with indexes of obesity and leptin after weight loss. IL-6 concentrations did not correlate with estradiol, systolic and diastolic blood pressure, and heart rate. Changes in IL-6 concentrations correlated significantly with changes in BMI (r=0.25, P<0.05). An improved body composition induced by restriction of energy intake and increase in physical activity is associated with more favorable serum concentrations of IL-6 in obese children and adolescents.