What is the primary function of the liver in metabolism?

The primary function of the liver in metabolism is to regulate blood glucose levels. The liver plays a central role in maintaining glucose homeostasis, which is crucial for providing a steady supply of glucose to the body, especially between meals and during periods of fasting. It achieves this through several processes, including glycogenesis (the conversion of glucose to glycogen for storage), glycogenolysis (the breakdown of glycogen back into glucose), and gluconeogenesis (the synthesis of glucose from non-carbohydrate sources).

While the liver does perform other important functions, such as producing bile, storing vitamins, and synthesizing proteins, these processes are not as central to metabolic regulation as the management of blood glucose levels. Therefore, the liver's ability to adjust glucose production and storage in response to hormonal signals allows it to effectively regulate overall metabolic balance and energy supply for the body.