Definition of "insulin" []

• A polypeptide hormone secreted by the islets of Langerhans and functioning in the regulation of the metabolism of carbohydrates and fats, especially the conversion of glucose to glycogen, which lowers the blood glucose level. (noun)
• Any of various pharmaceutical preparations containing this hormone that are derived from the pancreas of certain animals or produced through genetic engineering and are used in the medical treatment and management of diabetes mellitus (type I). (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Unfortunately, if insulin levels are always high, then the sensitive insulin receptors on your body¹s cells eventually become unresponsive to insulin, resulting in a host of problems related to what is called ³insulin insensitivity²."
• "REESE: Well, 16 million people have what they call insulin resistance, 60 million people have it, but 16 million are definitely going to have to deal with type 2 diabetes."
• "Type 2 diabetes is a condition in which patients are able to produce a hormone called insulin, which is needed to metabolize blood sugar or glucose, but somehow cannot use insulin effectively."