Small Intestine Function Overview

By leslie

Reviewed: dr. stavarache

Article Sources

Article Sources

• 1. ’The Structure and Function of the Digestive System.’ Cleveland Clinic, www. my.clevelandclinic.org/health/articles/7041-the-structure-and-function-of-the-digestive-system
• 2. Collins J; Nguyen A; Badireddy M. ‘Anatomy, Abdomen and Pelvis, Small Intestine.’ National Institutes of Health, www.pubmed.ncbi.nlm.nih.gov/29083773
• 3. ’Krause W. Brunner’s glands: a structural, histochemical and pathological profile.’ National Library of Medicine, www.pubmed.ncbi.nlm.nih.gov/11148980
• 4. ’Your Digestive System and How it Works.’ National Institute of Diabetes and Digestive and Kidney Diseases, www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works
• 5. ’Easton J. ‘Specific bacteria in the small intestine are crucial for fat absorption.’ The University of Chicago, uchicagomedicine.org/forefront/gastrointestinal-articles/specific-bacteria-in-the-small-intestine-are-crucial-for-fat-absorption
• 6. ’Small intestinal bacterial overgrowth.’ Mayo Clinic, www.mayoclinic.org/diseases-conditions/small-intestinal-bacterial-overgrowth/symptoms-causes/syc-20370168

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As the small intestine is responsible for most of the body's food digestion and absorption, it plays a critical role in the body's upkeep. Its length of about 20 feet provides ample space to get the job done.

The small intestine functions with the help of enzymes and bile, and its muscular outer layers move the food along to the large intestine, also known as the colon. Infections or inflammation in the small intestine from diseases, such as Crohn's disease, may interrupt the natural cycle of digestion, causing pain, elimination problems and sometimes, malnutrition.

The Small Intestine Food Journey

When food enters the mouth, chewing and saliva break it into small pieces and move it through the entrance to the duodenum, the first segment of the small intestine. Food travels from the duodenum to the longest part of the small intestine, the jejunum. In the jejunum, food mixes with bile from the liver and enzymes from the pancreas to get digested.¹’The Structure and Function of the Digestive System.’ Cleveland Clinic, www. my.clevelandclinic.org/health/articles/7041-the-structure-and-function-of-the-digestive-system

The jejunum moves the digested food to the ileum segment while absorbing sugars, amino acids and fatty acids. In the ileum, final nutrients, including B12 and bile acids, are absorbed. The ileum then dumps waste into the large intestine.²Collins J; Nguyen A; Badireddy M. ‘Anatomy, Abdomen and Pelvis, Small Intestine.’ National Institutes of Health, www.pubmed.ncbi.nlm.nih.gov/29083773