hormone secreted by the isles of Langerhans in the pancreas; regulates storage of glycogen in the liver and accelerates oxidation of sugar in cells
"The body relies on insulin, a hormone secreted by the pancreas, to regulate how the liver stores glycogen and speeds up sugar oxidation within its cells."
A polypeptide hormone that regulates carbohydrate metabolism.
"Insulin is a polypeptide hormone that regulates carbohydrate metabolism by facilitating glucose uptake into cells."
In plain English: Insulin is a hormone that helps your body turn sugar from food into energy for its cells to use.
"Diabetics must take insulin every day to manage their blood sugar levels."
Usage: Insulin refers specifically to the medication used by people with diabetes, not the biological hormone itself in general conversation. It is always treated as an uncountable noun and should never be pluralized when discussing the drug supply or dosage types.
The name insulin comes from the Latin word insula, meaning "island," because it was discovered in the pancreatic islands known as the Islets of Langerhans. The suffix -in was added to form the medical term for this substance.