The Small Intestine

The small intestine is where most of the magic of digestion happens. After food leaves your stomach, it enters this long tube. Here, your body absorbs the vitamins and nutrients it needs.

How It Works

Food moves through the small intestine slowly. The walls of the small intestine are covered in tiny finger-like bumps called villi. Villi absorb nutrients and pass them into your blood.

The blood then carries these nutrients to every part of your body. This is how your cells get the energy and building blocks they need.

A Very Long Tube

Even though it is called small, the small intestine is very long. In a kid, it can be about 16 feet long. In a grown-up, it can be over 20 feet long. It is called small because it is narrower than the large intestine.

The small intestine is coiled up inside your belly to fit. It takes food about three to five hours to travel through it.

Fun Facts

• If you unfolded all the villi in your small intestine, they would cover a tennis court.
• The small intestine absorbs about 90 percent of the nutrients from your food.
• Food is pushed through the small intestine by waves of muscle squeezing called peristalsis.

Did You Know?

The small intestine is the longest organ inside your body, even though it is all coiled up in your belly!