It has been shown that estradiol exerts favorable effects on insulin and glucose metabolism in vivo, such as increase in pancreatic insulin secretion [6], improvement of peripheral sensitivity to insulin [7], reduction of blood glucose and basal insulinemia [8], increased afterload blood glucose [9], improvement of the lipid effects of insulin [10], prevention of β-pancreatic cell apoptosis [11], and prevention of obesity [12]. This evidence concerns the gene INS and obesity due to melanocortin 4 receptor deficiency.