One of these common items might be the culprit behind your discomfort.

Your best friend’s gone gluten-free, another avoids dairy and your coworker swore off soy years ago. Thanks to skyrocketing diagnosis rates, hyper-awareness of food allergies, intolerances and sensitivities is now at fever pitch.

That’s a good thing for anyone plagued by food allergy-induced headaches, digestive woes or fatigue. But although the solution seems simple—all you have to do is cut out the offender, whether it’s gluten, soy or dairy—it’s not quite so straightforward.

“As we eat more processed foods, we’re unknowingly consuming all kinds of ingredients, making it harder to pinpoint what’s bothering you,” says New York dietician Tamara Freuman, R.D., who specializes in medical nutrition therapy for digestive disorders.

So if eliminating gluten, soy and dairy hasn’t alleviated your stomach troubles, consider removing one of the following foods that could be the true culprit behind that funny feeling in your gut.