The colon is about one and a half metres long and plays a vital role in moving waste through the body. In rare cases, it can become so stretched that it begins to lose its ability to work properly, like an elastic band that has lost its spring.
This is known as megacolon. Megacolon is not a single disease, but a term used to describe a colon that has become much wider than normal. The cause is important: some forms develop gradually, while others can become life-threatening within days.