About The Colon
The mixture of water, left-over nutrients, and waste now moves to the large intestine, or the colon. The colon's main job is to absorb water and store stool. There are two main types of movements in the colon.
First a back-and-forth motion helps the colon absorb fluid from the stool. At this point, bacteria that lives in the colon help break down any sugars left in the mixture. The colon absorbs water, nutrients, and salts, leaving behind solid stool.
Second, strong rhythmic contractions help move the stool through the colon into the rectum. This often happens after eating a meal. It normally takes a couple of days for stool to move through the colon. Stool is usually brown in color, but can vary from person to person, depending on what you eat.