What is celiac disease? Celiac disease is a genetic disorder that affects your digestive system and damages your small intestines. If you have celiac disease, your body is sensitive to gluten and your immune system reacts abnormally to foods you eat that contain gluten. Gluten is a protein found in foods and products that contain certain grains, such as wheat, oats, barley and rye. The lining of your intestines is made of many small fingerlike bumps, called villi, that are responsible for digesting and absorbing nutrients. In celiac disease, the villi flatten out and are damaged or destroyed when exposed to gluten. This decreases the amount of surface area that is available to digest and absorb nutrients in the small intestine. The symptoms of celiac disease vary among individuals and depend on the amount of gluten a person consumes. Symptoms can affect the digestive tract as well as other parts of the body. Common symptoms include excessive gas, abdominal bloating, diarrhea, weight loss, and fatigue. Some people who have celiac disease may have no symptoms. Celiac disease, also known as celiac sprue or gluten-sensitive enteropathy, is far more common than once believed. According to the National Institutes of Health, more than two million people in the United States are affected by celiac disease. It commonly runs in families and in populations with other autoimmune diseases and genetic disorders (Source: NIDDK). What’s the difference between celiac disease and gluten intolerance? Celiac disease is a serious form of gluten intolerance in which the body reacts to gluten by damaging the small intestine. Although the symptoms can be similar, celiac disease symptoms are generally more severe and long-lasting compared to the symptoms of milder forms of gluten intolerance. Most importantly, celiac disease causes actual damage to the small intestine and can cause complications in other body systems, such as anemia and osteoporosis. These problems are generally not seen in milder forms of gluten intolerance. Left untreated, celiac disease can result in serious complications, such as malnutrition, small intestine cancer, and anemia. Seek prompt medical care if you have symptoms of celiac disease, such as excessive abdominal bloating, diarrhea or weight loss.