(AP) — In this Thursday, July 14, 2012 photo, Bertha Domimguez prepares gluten-free dough at Pure Knead bakery sandwich bread in Decatur, Ga.
Scientists suggest that there may be more celiac disease today because people eat more processed wheat products than in decades past, which use types of wheat that have a higher gluten content. Or it could be due to changes made to wheat, said the Mayo Clinic's Dr. Joseph Murray. In the 1950s, scientists began cross-breeding wheat to make hardier, shorter and better-growing plants. It was the basis of a so-called "Green Revolution" that boosted wheat harvests worldwide. (AP Photo/John Bazemore)