Britannica Sources used in this answer

How do insulin and glucagon help control blood glucose levels?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

A woman with curly hair and a handbag shops at a busy outdoor farmer's market in Bulgaria, surrounded by stalls filled with fresh fruits and vegetables. — nutrition Vegetables are an important part of a balanced diet.

Insulin and glucagon are pancreatic hormones that work in opposition to maintain blood glucose homeostasis.

Insulin is secreted by beta cells in the islets of Langerhans when blood glucose levels rise. It lowers blood sugar by:
* Promoting the uptake of glucose into muscle and adipose tissue.
* Encouraging the storage of glucose as glycogen in the liver and muscles.
* Decreasing gluconeogenesis, the production of glucose from non-carbohydrate sources.1

Glucagon is secreted by alpha cells in the islets of Langerhans, typically in response to low blood glucose or during exercise. It raises blood sugar by:
* Stimulating glycogenolysis, the breakdown of stored glycogen into glucose.
* Promoting gluconeogenesis in the liver to release new glucose into the bloodstream.2

Together, these hormones function through a negative feedback system to ensure that blood glucose concentrations remain within a stable range, providing a consistent energy supply for the body.21