Which hormone regulates glucose levels in the blood?

Insulin plays a crucial role in regulating glucose levels in the blood. It is produced by the pancreas in response to elevated blood glucose levels, such as after eating a meal. Insulin facilitates the uptake of glucose by cells, particularly in muscle and fat tissues, allowing for the reduction of glucose in the bloodstream. By promoting the storage of glucose as glycogen in the liver and muscle, insulin helps to maintain homeostasis and a stable blood glucose level.

Other hormones mentioned can influence blood glucose levels but do not play the primary regulatory role that insulin does. For example, adrenaline increases blood glucose levels by promoting glycogenolysis, while cortisol is involved in gluconeogenesis and can also raise blood sugar. Glucagon serves to increase blood glucose levels when they are low by stimulating the liver to release stored glucose. However, insulin is the key hormone for bringing glucose levels down after they rise.