This observation supports the view raised in our previous review article [51] that screening for prediabetes should include fasting and postprandial blood insulin levels along with blood glucose levels; Moreover, to prevent the islet morphological alteration from becoming irreversible, or to prevent T2D pathological progression from irreversible, certain pharmacological intervention should be taken at as early as the stage of hyperinsulinemia even with euglycemia. Here, INS is linked to type 2 diabetes mellitus.