IGF1 and Tangier disease: Although the liver mainly produces IGF-1, every tissue can secrete IGF-1 for autocrine and paracrine purposes.3 IGF-1 possesses a large number of activities (anabolic, antioxidant, anti-inflammatory and cytoprotective actions), however, it is partly responsible for systemic GH actions.4 IGF-1 deficiency in TM patients in children and adolescents has been attributed to chronic anemia and hypoxia, chronic liver disease, iron overload and other associated endocrinopathies, e.g. growth hormone deficiency (GHD).5–11