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Everyone knows someone who refuses to eat certain foods, whether it’s because of yucky texture, unappetizing color or stinky smell. Usually these people are kids. But according to a preliminary online survey by researchers at the Duke University Center for Eating Disorders, extremely picky eating may be more common in adults than you think.

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Researcher Nancy Zucker at Duke says these exceptionally picky adults may be suffering from a previously unrecognized illness called selective eating disorder (SED). They’re not just being bratty, Zucker tells LiveScience’s Robin Nixon. Rather, selective eaters may experience food differently than other people: they tend to reject food because of look or smell, rather than taste, and they often have had early negative associations with food, like stomach problems or acid reflux in infancy, LiveScience reports. The condition can cripple people’s social lives and affect long-term mental health. Nixon writes about one such picky eater:

He’s 63 years old, but Bob Krause admits he still eats “a 4-year-old’s dream diet.” Krause likes peanut butter, crackers, grilled cheese sandwiches, chocolate milk and little else. More adventurous meals look like “a plate of barf,” he told LiveScience. “If I could snap my fingers and change, I would,” he said, explaining his pickiness helped ruin two marriages, limited his career options and makes most social occasions sources of stress.

Selective eaters tend to have similar “safe” foods, Nixon reports, typically the same foods they enjoyed in childhood: French fries and bacon, for instance; no fruits or vegetables. Foods outside the safe zone are perceived as repulsive. (More on Time.com: Overeating: Is It an Addiction?)

It’s unknown how many extremely picky adult eaters are out there — they try to hide their food issues and avoid social situations that center around food — but if it’s any indication, in less than five months, Zucker’s extensive Food FAD Study (Finicky Eating in Adults) logged more than 7,500 registrants online; even more people started the survey but didn’t finish.

According to Nixon’s article, Zucker plans to do a formal analysis of the survey data next year, and perhaps further explore whether the condition has some biological cause, or is a result of disordered psychology. The survey suggests that it is distinct from other disorders, such as obsessive-compulsive disorder, anorexia or bulimia. (More on Time.com: Study: Some Benefits of Probiotics for Kids)

The American Psychiatric Association is considering adding adult selective eating disorder to the fifth edition of its Diagnostic and Statistical Manual of Mental Disorders, which is due out in 2013, although a final decision has yet to be made.

Until then, those who are experiencing symptoms of SED can consult their doctors and find support on sites such as PickyEatingAdults.com (run by Krause), where visitors can share stories and connect with other adults who have the same propensity for finicky eating — and French fries. (More on Time.com: 5 Ways to Get Oatmeal in Your Diet, Deliciously)

For more on selective eating, and tips to help kids from becoming picky adult, see the full LiveScience story here.

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