Childhood obesity is an important risk factor for the development of insulin resistance (IR) and its co-morbidities. However, visceral adipose tissue (VAT) rather than obesity appears to have a determining role in the development of IR. Adiponectin is considered a key molecule for protection against metabolic abnormalities related to IR. Several studies have documented that lower adiponectin concentrations are related to VAT, but the results are still controversial. We undertook this study to assess the association between VAT and adiponectin concentrations with respect to body mass index (BMI) and pubertal stage in children and adolescents. Eighty five subjects were studied (46 prepubertal and 39 pubertal) and classified according to BMI into obese and normal weight groups. All participants were given a clinical examination. Glucose, insulin, lipid profile and adiponectin were measured. VAT was estimated using helical computed tomography. In the prepubertal group, obese children had lower adiponectin concentrations than nonobese subjects (p