Gluten grains contains compounds called exorphins which are addictive and leave many people in denial about negative impact these grains have on health and digestion. (grassfedgirl.com)
Incomplete digestion of gluten and casein may result in the production of exorphin (exogenous opiate - like) polypeptides that have the capacity to cause or potentiate adverse neurological symptoms. (appliedhealth.com)
This is preferred because if these proteins are not broken down enough in the stomach, exorphin peptides can be created in the small intestine. (pethealthandnutritioncenter.com)