What is an ileostomy the role the intestines in absorbing nutrients from food and the removal of waste from the body is an essential factor in the maintenance of good health both the mall intestine and large intestine are major components of the overall gastrointestinal tract the small intestine runs the and if the stomach to the beginning up the large intestine and is in involved in the absorption of nutrients from ingested food the small intestine has three main parts the duodenum digit jejunum and the ileum