The small intestine is hardly small at all. At about 7 miters (22.97 feet) in length it exceeds the length of the large intestine 4 to 5 times. The small intestine is however much narrower in diameter, about 2.57 miters. This is largely due to the unique function of the small intestine, which is part of the digestive and absorption process, along with the mouth and stomach. The large intestine, or colon, functions primarily in the elimination process and deals with the bulk which the body cannot use, which is why it is much shorter, but wider in width. The small intestine fits in the center of the abdomen, curved and coiled in its space, and is surrounded on three sides by the large intestine.

Unlike the outer walls of the small intestine, the inner walls are made up of two kinds of wrinkles and folds called plicae circulares and rugae. The plicae circulares are a fixed feature of the small intestinal walls, while the rugae allow extra tissue for the small intestine to distend and contract as needed. The plicae circulares have two kinds of microscopic textures called villi (a Latin word meaning "shaggy hair") and microvilli. The microvilli covers the villi like a velvet coating. These two kinds of fine, frond-like protrusions work together, to maximize the small intestine surface, for ultra efficient nutrient absorption. Each villus is the home of lacteal and capillaries, which are close to the surface, and absorb fats and nutrients.

The small intestine has three sections, each with its own specific function. They are the:

Duodenum: (26 cm or 9.84 inches) The duodenum (from the Latin words duodenum digitorum, or “twelve fingers' breadths”) is the first section of the small intestine, and is connected to the stomach. Its function is to begin the breakdown of food for the following sections of the small intestine.

Jejunum: (2.5 m or 8.2 ft.) The Jejunum (meaning “fasting”) has the function of absorbing most nutrients into the bloodstream.

Ileum: (3.5 m or 11.5 ft) The ileum absorbs vitamin B12, bile salts, and the final processing of proteins and carbohydrates. It is the last part of the small intestine, and connects to the large intestine.

Please see my related articles:
Stomach Function
Digestion and Liver Function


*Please know that I am not a medical doctor or a health practitioner. I cannot diagnose your stomach problems nor can I guarantee a cure. I am here to share my knowledge, which applications have worked for me and to offer suggestions of where you may go physically, emotionally and spiritually for healing and self-empowerment. If you choose to explore alternative medicine, do not independently stop taking your prescribed medications. Always consult with your current doctor as well as your new practitioner when changing your medical program