Small intestine

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The small intestine is a winding, tightly folded tube about 20 ft (6.1 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 food.

Current as of: October 19, 2023

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: October 19, 2023

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.