Title: What is the function of the small intestine? | Digestive Health - Sharecare
Headings: What is the function of the small intestine?
What is the function of the small intestine?
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Content: As the food moves through the jejunum it continues being digested and takes on a more fluid state. The ileum is the longest part of the small intestine and the part from which most nutrients and liquid are absorbed from food, before the remainder of the food is deposited into the large intestine. Dr. William B. Salt, MD
Gastroenterologist
The small intestine is 15 to 20 feet long and includes three sections: the duodenum (which makes up the first 10 inches of the small intestine)
the jejunum (which makes up the next 5 feet)
the ileum (which makes up the rest). Digestion and absorption of food take place primarily in the small intestine. In the duodenum, bile and pancreatic juice are added to the food mixture. In the jejunum, fat, starch and proteins from the food material are broken down and absorbed by the intestinal lining. The lining is covered with millions of tiny villi, or finger-like projections, that greatly increase the surface area, allowing nutrients to be more efficiently absorbed into the bloodstream. In the ileum, which is the last part of the small intestine, water and nutrients (such as vitamin B12) are absorbed. Bile, which is released by the gallbladder into the duodenum in order to help emulsify (digest) ingested fats, is reabsorbed in the ileum to prevent its loss from the body.