Celiac disease (CD) is a common digestive disease. It is also known as celiac sprue, gluten-sensitive enteropathy, or nontropical sprue. In individuals with CD, gluten (a protein in wheat, barley, and rye) damages the small intestine and results in difficulty absorbing nutrients from food. Up to 1 in 113 people in the United States have CD. The risk is higher (1 in 22) in people with a first-degree relative with CD. The cause of CD is unknown, but environmental, immunologic, and genetic factors all contribute. The October 12, 2011, issue of JAMA includes an article about CD. This Patient Page is based on one originally published in the September 16, 2009, issue of JAMA .