Background
Insulin is a hormone that regulates the amount of glucose (sugar) in the
blood and is required for the body to function normally. Insulin is
produced by cells in the pancreas, called the islets of Langerhans. These
cells continuously release a small amount of insulin into the body, but
they release surges of the hormone in response to a rise in the blood
glucose level.
Certain cells in the body change the food ingested into energy, or blood
glucose, that cells can use. Every time a person eats, the blood glucose
rises. Raised blood glucose triggers the cells in the islets of Langerhans
to release the necessary amount of insulin. Insulin allows the blood
glucose to be transported from the blood into the cells. Cells have an
outer wall, called a membrane, that controls what enters and exits the
cell. Researchers do not yet know exactly how insulin works,