In the present study, HOMA-IR and fasting blood insulin levels were significantly higher in hypothyroid children and adolescents with or without obesity compared to the control group, which is consistent with the results of previous studies indicating that hypothyroidism can induce IR and this IR is related to hypothyroidism more than BMI [7–9, 11–14]. This evidence concerns the gene INS and obesity due to melanocortin 4 receptor deficiency.