ELI5: What is insulin and how does it works?

Imagine you eat a yummy cookie. That cookie has sugar in it, which your body breaks down into something called glucose. Glucose is like fuel for your body, giving you energy to play and run around.

Now, glucose needs to get inside your body's cells (like tiny rooms) to give them that energy. But glucose can't get in by itself! It needs a special key called insulin.

Insulin is made by a special part of your body called the pancreas. Think of the pancreas as a tiny factory that makes these insulin keys.

Here's how it works:

• You eat your cookie, and your blood sugar (glucose levels) goes up.
• Your pancreas sees the sugar level rising and starts making more insulin.
• Insulin travels through your blood and finds the cells that need energy.
• Insulin acts like a key to unlock a door on the cell.
• The glucose can now enter the cell and give it energy!
• Once the glucose is inside the cells, your blood sugar goes down.
• The pancreas stops making so much insulin.