The small intestine is a winding, tightly folded tube about 20
ft (6 m) long in adults. It is connected to the stomach on the top end and to
the large intestine (colon) on the bottom end.
Most of the food a person consumes is digested and absorbed in
the small intestine. The lining of the small intestine has tiny finger-shaped
raised tissues (villi). These raised tissues greatly increase the surface area
of the intestine, which absorbs calories and nutrients from