What is the primary function of glucagon in the body?

The primary function of glucagon in the body is to promote glucose release by the liver. When blood sugar levels drop, glucagon is secreted by the alpha cells of the pancreas. It signals the liver to convert stored glycogen into glucose through a process called glycogenolysis and to release this glucose into the bloodstream. This action is crucial for maintaining blood sugar levels within a normal range, especially during fasting or intense physical activity.

Glucagon essentially acts as a counter-regulatory hormone to insulin, which lowers blood sugar levels. By facilitating the release of glucose from the liver, glucagon helps to ensure that the body has a continuous supply of energy, particularly for vital functions and for tissues like the brain that require glucose to function optimally.