Celiac disease -- an allergic reaction to gluten - is four times more common today than it was 50 years ago, according to research conducted at the Mayo Clinic.
Mayo gastroenterologist Joseph Murray says one in 100 people now have the disease.
He says doctors had thought the marked increase was a result of better screening, but the research suggests that celiac disease is truly becoming more common, paralleling other diseases like type one diabetes or allergies.
Murray says that suggests this could be an autoimmune response, or it could be that something has changed about gluten.
"When it's not busy fighting infections in our environment it's up to no good and turns on ourselves or create autoimmunity. That's one theory," he said. "Celiac disease is unusual in that we know the environmental trigger for the disease. You have to eat gluten, the protein from wheat, barley or rye to get the disease. So another possibility is that something changed about gluten."
People with untreated celiac disease are also four times more likely to die earlier than people without the disease. Murray says people of all ages can develop the disease.