In the present study, we have decided to analyse the metabolic profile (insulin resistance and lipids) in two untreated groups of GHD patients: (1) with lower (worse) IGF-I bioavailability and (2) with higher (better) IGF-I bioavailability, and we have tried to evaluate the additional role of nutritional state, as well as ghrelin, leptin, adiponectin, and resistin on metabolic profile in these groups. Here, RETN is linked to Insulin resistance.