Carbohydrate metabolism is tightly regulated by a coordinated interplay of hormones that maintain blood glucose homeostasis within a narrow physiological range. The primary site of regulation is the liver, along with skeletal muscle and adipose tissue, where processes such as glycogenesis, glycogenolysis, glycolysis, and gluconeogenesis are dynamically controlled according to the body’s energy needs. Among all hormones, insulin and glucagon play the central antagonistic roles, while epinephrine, cortisol, growth hormone, and thyroid hormones provide additional layers of regulation during stress, fasting, and varying metabolic demands. Insulin, secreted by the β-cells of the pancreas in response to elevated blood glucose levels, is the principal anabolic hormone in carbohydrate metabolism. It promotes glucose uptake in insulin-sensitive tissues such as skeletal muscle and adipose tissue by facilitating the translocation of GLUT4 transporters to the cell membrane. In the liver and muscle, insulin stimulates glycogenesis by activating glycogen synthase and inhibiting glycogen phosphorylase, thereby promoting storage of glucose as glycogen. It also enhances glycolysis by stimulating key regulatory enzymes like phosphofructokinase-1 and pyruvate kinase. In addition, insulin suppresses hepatic gluconeogenesis by inhibiting enzymes such as phosphoenolpyruvate carboxykinase and glucose-6-phosphatase, thereby reducing endogenous glucose production. Glucagon, secreted by α-cells of the pancreas during hypoglycemia, has the opposite effect of insulin. It primarily acts on the liver to increase blood glucose levels by stimulating glycogenolysis and gluconeogenesis. Through activation of adenylate cyclase and increased cyclic AMP, glucagon activates protein kinase A, which in turn phosphorylates and activates