What is Celiac disease and how does it affect us? Celiac disease is a state in which the lining within the walls of the small intestine are prevented from absorbing crucial food elements needed for the overall health of the body. The lining of the intestinal walls have sections containing villi, which assist in the body absorbing the nutrients as they pass through the area. As a result of the immune systems attack against the glutens found in the food that is eaten, the villi in those walls are damaged. Irrespective of how much food is consumed by the patient, the lining in those intestinal walls will not absorb the nutrients, leaving the patient to suffer the effects of malnutrition in spite of large volumes of food being eaten. It occurs when the patient consumes cereals such as barley, wheat, rye, and even oats which contain gluten although the exact cause of Celiac disease is generally not known.