A little pouch under the liver
Your gallbladder is a small pouch shaped like a pear. It's tucked under your liver, on the right side of your belly.
It's hollow, like a tiny balloon. It holds bile, the yellow-green juice your liver makes.
In a grown-up it's about 3 to 4 inches long, and it holds only a few tablespoons of bile.
Squeezing out bile
Your liver makes bile all the time. Between meals, extra bile goes into the gallbladder to wait.
While the bile waits, the gallbladder takes out some of its water, so the bile gets stronger.
When you eat food with fat in it, like cheese, eggs or nuts, a message tells the gallbladder to squeeze. Bile flows down a small tube into your small intestine, where it breaks fat into tiny drops, like soap on a greasy dish.
Living without a gallbladder
The gallbladder is helpful, but you can live without it. Some grown-ups have theirs taken out by a doctor.
After that, bile just flows straight from the liver into the small intestine, and digestion still works.