Science
How does insulin work?
Insulin is a hormone that lets your body use sugar for energy. After you eat, it signals cells to absorb glucose from the blood, keeping blood sugar in a healthy range. Without enough insulin, sugar builds up — the basis of diabetes.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how insulin works.
Step by step
- 1Insulin is a hormone made by the pancreas.
- 2It acts like a key, letting cells take in glucose from the blood.
- 3This lowers blood sugar and stores energy for later.
- 4Too little insulin (or resistance to it) causes diabetes.
Frequently asked questions
- What does insulin do in the body?
- It signals cells to absorb glucose from the blood, lowering blood sugar and supplying cells with energy.
- What happens without enough insulin?
- Glucose can't enter cells properly, so it builds up in the blood — the core problem in diabetes.
- Where is insulin made?
- In the pancreas, by clusters of cells called the islets of Langerhans.