Changes in hepatic risk factors, metabolic variables, body composition, and physical fitness in obese children after a one-year weight loss program.

Obesity can cause insulin resistance and cardiovascular and liver disease. The aim of this study was to analyze changes in laboratory values, body composition, and physical fitness before and after a one-year weight loss program with nutritional education, psychological care, and physical exercise. Twenty-two obese children (16 boys, 6 girls; median age 11.9 [range 7-15] years; BMI SDS +2.4 [1.6-3.1]) participated in the program. Outcome measures included liver enzymes, insulin resistance (HOMA), lipids, body composition, physical strength and endurance. All children had an inverse HOMA/body composition correlation; Group 1 (reduced BMI SDS after one year) had lower triglycerides, liver enzymes and improved body composition and fitness (p < 0.05). Group 2 (unchanged or increased BMI SDS) had worse body composition and increased endurance and strength of trunk extension (p < 0.05). Weight loss reduced risk factors for liver disease and improved insulin sensitivity. Body composition proved useful as a non-invasive indicator for insulin sensitivity.