INS and Hyperglycemia: Importantly, through the protection of β-cells and stimulation of insulin production, genistein is also able to reduce hyperglycemia in diet-induced obesity models (e.g., in STZ treated C57BL/6 mice on a high-fat diet—HFD), ovariectomized rats, and in genetically obese diabetic (db/db) mice, which share the metabolic characteristics of human T2D manifested with insulin resistance and reduced β-cell mass and function [39,40,41].