A study led by researchers at Columbia University may have found the biological reason some people who do not have celiac disease still get intestinal and other symptoms when they eat gluten-containing foods.

The study, published in the medical journal Gut, details the differences in immune system reactions between those who have celiac disease and those who react to gluten even though they do not have the blood, tissue and genetic markers of celiac disease. The study suggests that those with gluten sensitivity may have a weakened intestinal barrier, which leads to a body-wide inflammatory immune response.

Study co-author Peter H. Green, MD, director of the Columbia Celiac Disease Center, said in a press release that the study shows symptoms of gluten sensitivity “are not imagined, as some people have suggested.”

The study findings may lead to ways to identify patients with gluten sensitivity and to monitor their response to treatment, said study leader Armin Alaedini, PhD, assistant professor of medicine at Columbia.

You can read more about the study here.