Where is your spleen?
Your spleen sits on the left side of your belly, up under your ribs, near the back of your stomach. Your ribs help keep it safe.
It's soft and purplish, and in a grown-up it's about the size of a fist. Like the rest of you, it grows as you grow.
The blood filter
Red blood cells carry oxygen all around your body. Each one lasts about 120 days, roughly four months. Then it gets old and stiff.
Blood flows through your spleen all the time. The spleen catches the old red blood cells and breaks them down.
Nothing goes to waste! The iron from old red blood cells gets sent back to your bone marrow to help make new ones.
A germ-fighting station
Your spleen is part of your immune system, the team that protects you from germs.
It stores white blood cells, your body's germ fighters. When germs show up in your blood, the spleen helps spot them and sends fighters to attack.
It also keeps a stash of platelets, the tiny cells that help a cut stop bleeding.
Living without a spleen
If a spleen is badly hurt or sick, doctors can take it out. People can live without a spleen.
Other parts, like the liver, take over some of its jobs. People without a spleen may get a few extra shots and checkups to help their body fight germs.