If you have celiac disease and eat foods with gluten, your immune system responds by damaging the small intestine. Gluten is a protein in wheat, rye and barley. It is found mainly in foods but may also be in other products like medicines, vitamins and even the glue on stamps and envelopes. Celiac disease affects each person differently. Symptoms may occur in the digestive system, or in other parts of the body. One person might have diarrhea and abdominal pain, while another person may be irritable or depressed. Irritability is one of the most common symptoms in children. Some people have no symptoms. (Read more) | ![]() |