Celiac disease is an immune reaction to eating gluten, a protein found in wheat, barley, and rye. For those with the disease, eating gluten triggers an immune response in the small intestine. Over time, this immune reaction damages the small intestine's lining and hinders absorption of some nutrients. The intestinal damage often causes stomach pain, diarrhea, and weight loss, and can lead to serious complications. A Mayo Clinic-led analysis published in 2012 estimates that roughly 1.8 million Americans have the disease, but around 1.4 million of them are unaware that they have it.

- Committee on Divine Worship Newsletter, October 2012.