What Is the Main Function of the Large Intestine?

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The main function of the large intestine is to absorb water and remove solid waste from the body. The organ takes approximately 16 hours to complete the digestion of food. This organ is the last part of the digestive system and stretches from the ileocecal valve to the anus.

The large intestine is made up of the ascending colon, transverse colon, descending colon, sigmoid colon, rectum and anal canal. The beginning of the large intestine, or the iliac region, is just below the waist. The organ joins to the end of the small intestine at this point, then actually travels up the abdomen cavity before turning to cross the entire cavity just below the stomach. Once it crosses the cavity, it drops back down the length of the abdomen, reaching all the way to the anal canal and anus. Even though it is called the large intestine, it is shorter in length than the small intestine, which varies between 22 feet 8 inches in men and 23 feet 4 inches in women. The large intestine is almost 5 feet long, which is only around one-fifth of the digestive systems entire length. While food travels this length, not only does the large intestine remove water, but it also removes any remaining usable nutrients. It also absorbs the vitamin K created by the colonic bacteria.