Vitamin D Supplementation in Vitamin D Deficient Obese Children During Weight-loss Program

1. Analyze the influence of vitamin D supplementation in obese children during weight-loss program on BMI, body composition and bone mineral density. 2. Analyze the influence of vitamin D supplementation on the risk profile of obesity-related complications, namely impaired tolerance of glucose, insulin resistance, dyslipidemia and arterial hypertension, in obese children participating in weight-loss program. 3. Analyze the prevalence of vitamin D deficiency among obese children. 4. Analyze the risk factors of vitamin D deficiency in obese children (age, gender, pubertal status).