ITLN1 and type 2 diabetes mellitus: A clinical study in forty-six patients with impaired glucose tolerance (IGT), fifty-five patients with newly diagnosed type 2 diabetes mellitus (T2DM), and fifty subjects with normal glucose tolerance (NGT) found that omentin concentrations were lower in patients with IGT and T2DM than patients with NGT, with the lowest concentrations observed in those with T2DM(28).