The following four main results were obtained: 1) the KITT(iv) of patients with T2DM was 2.5%±2.1%, which was significantly lower than that of the controls (4.5%±1.8%); 2) KITT(iv) was significantly correlated with the HOMA-IR value but not with KITT(sc); 3) KITT(iv) was significantly correlated with VFA and the serum glucose, CPR, TNF-α, BCAA/total AA, and adiponectin concentrations; and 4) the total insulin dose required for glycemic control was correlated with KITT(iv) and the HOMA-IR value, and it was estimated using an equation in patients with T2DM. This evidence concerns the gene ADIPOQ and type 2 diabetes mellitus.