Gluten enteropathy, also known as celiac disease, is an autoimmune disorder caused by the ingestion of gluten. Gluten is a protein found in wheat, barley, and rye that humans lack the enzymes to properly break down. In celiac disease, the immune system mistakenly attacks and damages the villi of the small intestine upon exposure to gluten. This leads to inflammation, leaky gut syndrome as gluten passes through the damaged intestinal wall, and eventually the flattening and destruction of the microvilli lining of the small intestine.