Gluten, a kind of stretchy protein found in wheat, rye and other grains, is ubiquitous in processed food products because of its handy binding properties. That makes it hard to avoid. But who, exactly, needs to follow a gluten-free diet?
Certainly people who have celiac disease—roughly 1% of the population—since eating gluten triggers an intestine-damaging immune system response. It’s also a no-no for people who are allergic to wheat. For both of these groups, eating foods with gluten can lead to inflammation of the small intestines and symptoms like abdominal pain, funky bowel movements, foggy thinking, chronic headache, joint pain, skin rashes and chronic fatigue, says Dr. Alessio Fasano, director of the Center for Celiac Research and Treatment at Massachusetts General Hospital.
But there’s a third group of people who also go gluten free: those who experience many or all of the above symptoms in response to eating wheat or gluten, but who do not test positive for either celiac disease or a wheat allergy. Because these people tend to feel better when they avoid gluten, some experts refer to their condition as “non-celiac gluten sensitivity” (NCGS).
For a time, many doctors did not acknowledge that such a condition exists, and NCGS is still controversial. But Fasano and others say they’re now certain it’s a legitimate phenomenon, although its name may not be quite appropriate. “It’s probably a sensitivity to more than one ingredient in grains, so things besides just gluten are triggering the immune response,” he says.