According to a study of food allergies in adults, American researchers believe that a large percentage of us are making ours up.

According to new research, more than a fifth of adults believe they have a food allergy, but it is very possible they’re making it up.

As it turns out, very little is actually known about the prevalence and severity of food allergies among adults. While we’re able to accurately chart it in children, the adult-sized studies are surprisingly thin.

Despite this, not being able to eat something is a bankable force. Great forests of macro industries have cropped up as people have sought products that are dairy-free, gluten-free, peanut-free, et cetera. In 2010, sales of gluten-free products reached $2.6 billion, according to a CNBC report. Six years later, in 2016, California-based Grand View Research valued the global gluten-free product market at nearly $15 billion, with the US accounting for about half of that.

But, back to the research. Scientists at Stanford and Northwestern conducted a survey and teamed up to conduct a telephone and internet survey study of more than 40,400 American adults.

What they discovered, was telling. More people think they are living with food allergies when they actually aren’t. According to the study, 10% of Americans suffer from a diagnosed allergy, while 20% just think they have one.

While the researchers say there is still a lot to learn about food allergies, perhaps you should see a doctor and confirm your maladies prior to you loudly questioning the contents of a paella in a busy restaurant.

Yeah, I see you. Go on, be shellfish.