Celiac disease is a digestive condition triggered by consumption of the protein gluten, which is primarily found in bread, pasta, cookies, pizza crust and many other foods containing wheat, barley or rye. People with celiac disease who eat foods containing gluten experience an immune reaction in their small intestines, causing damage to the inner surface of the small intestine and an inability to absorb certain nutrients. Celiac disease can cause abdominal pain and diarrhea. Eventually, the decreased absorption of nutrients (malabsorption) that occurs with celiac disease can cause vitamin deficiencies that deprive your brain, peripheral nervous system, bones, liver and other organs of vital nourishment. No treatment can cure celiac disease. However, you can effectively manage celiac disease by changing your diet.