Celiac Sprue is a digestive disease that interferes with the digestion and absorption of nutrients in food. People with celiac disease cannot tolerate gluten. When exposed to gluten, the lining of the intestine becomes damaged. Gluten is found in foods that contain wheat, barley, rye and some oat products. Because a gluten-free diet restricts some essential nutrients, it is important to only embark on a gluten free diet under a doctor’s supervision. Supplements will be needed to fill in the nutritional gaps.