Description: used to detect colon cancer and other potential problems -- involves use of a long, flexible tube with a camera that takes images of the colon.

Before having a colonoscopy, you should follow certain do's and don'ts to ensure an accurate procedure. This list is provided by the U.S. National Digestive Diseases Information Clearinghouse:

Avoid all solid foods and any beverages with food coloring for one to three days before a colonoscopy.
You may eat fat-free bouillon or broth soups, or gelatin.
You may drink water, strained fruit juice, plain coffee, plain tea or diet soda (no food coloring).
As certain medications may affect your results, tell your doctor if you are taking aspirin, arthritis medications, blood thinners, medications for diabetes, or any vitamins containing iron.