The hormone that regulates blood sugar levels is insulin. Produced by the pancreas, insulin plays a crucial role in controlling blood glucose levels after meals. When blood sugar levels rise, insulin is secreted to facilitate the uptake of glucose by cells, allowing them to use it for energy or store it as glycogen in the liver and muscles. This regulatory mechanism prevents hyperglycemia, which can lead to diabetes and other health issues. In type 1 diabetes, insulin production is insufficient, while in type 2 diabetes, the body's cells become resistant to insulin's effects.