A single-blind study using plasma samples from 48 newly diagnosed T2DM patients and 48 non-diabetic individuals clearly indicated different glycation degrees characteristic of each glycation site with glycated Lys141 of haptoglobin providing the best sensitivities (~94 and ~78%) and specificity (~98%) when combined with HbA1c and FPG levels, respectively. Here, HP is linked to type 2 diabetes mellitus.