Insulin works like a special car that carries sugar (glucose) from the blood into your cells. All cells need sugar to get energy and do their jobs—just like cars need fuel to run.

This special car is made in a factory inside your body called the pancreas. Insulin controls how much sugar stays in your blood and how much it goes into your cells.

When there isn’t enough insulin, sugar stays in the blood, and the cells don’t get the energy they need.