Children who are overly selective about the foods they eat are more prone to anxiety and depression, researchers say.

To most parents, a young picky eater is merely going through a negative phase.

But, according to researchers at Duke University School of Medicine, the condition may be linked to depression and anxiety disorders.

According to their study, published today in the journal Pediatrics, more than 20 percent of children ages 2 to 6 are what the scientists call selective eaters. Most of that group was classified as moderately picky.

The remaining children, about 3 percent of all children, were classified as severely selective. Their food intake was so limited that it affected their ability to eat with others.

That meant a parent often had to produce a separate meal for them because they wouldn’t or couldn’t eat what the rest of the family had.

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Nancy Zucker, Ph.D., is the director of the Duke Center for Eating Disorders and lead author of the study. She stressed the importance of families and physicians determining when picky eating reaches problem proportions.

“The children we’re talking about are not just misbehaving kids who refuse to eat their broccoli,” she said in a press release.

The study found that both moderate and severe selective eating was associated with significantly elevated symptoms of depression, social anxiety, and generalized anxiety.

One conclusion that emerged from the study is the importance of more active communication by pediatricians and other clinicians while the child is still young, according to William Copeland, Ph.D., an associate professor of psychiatry at Duke and a co-author of the study.

“We need to help these parents,” he told Healthline. “We need to learn how [the child’s eating] affects the family and how to make referrals for further help.”

At the same time, pediatricians need to monitor the child. The picky eating may be a marker for emotional problems later on, Copeland said.

“Right now most parents aren’t getting any assistance,” he said.

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The study looked at preschool children with both moderate and severe selective eating habits who showed symptoms of anxiety and other mental conditions.

The study, which screened an initial 3,433 children coming to well-child clinics, also found that those with selective eating behaviors were nearly twice as likely to have increased symptoms of generalized anxiety at follow-up intervals.

Children with moderate and severe patterns of selective eating meet the criteria for Avoidant/Restrictive Food Intake Disorder, an eating disorder and a new diagnosis included in the most recent Diagnostic and Statistical Manual of Mental Disorders.

The study also found that selective eating was less common in African American families than in white ones. As Copeland noted, “We’re not sure what to do with that information.”

Zucker said some picky eaters might have heightened senses that can make the smell, texture, and tastes of certain foods overwhelming, causing aversion and disgust. For other children, the behavior is triggered by a bad experience with a certain food. They become anxious when confronted by another new food or being forced to try the offensive food again, she said.

Does picky eating cause other emotional problems or does the child start out vulnerable to different sorts of anxiety, including food issues?

“We don’t have all the answers,” Copeland said. “We don’t know if it’s cause and effect. We’re relatively certain there’s a link. Anxious kids may over-respond to feelings.”

More research needs to be done.

“There is not a simple silver bullet solution,” Copeland said.

Katherine K. Dahlsgaard, Ph.D., is the lead psychologist at the Anxiety Behaviors Clinic and director of the Picky Eaters Clinic, Department of Child and Adolescent Psychiatry and Behavioral Sciences, at the Children’s Hospital of Philadelphia.

She has treated many children with this problem.

In an article earlier this year for, she discussed some of the techniques that help families. One is repeated exposure to a new or unwanted food.

“Continuously motivating them to take one or two bites of that broccoli in their bowl despite their objections encourages children to open their minds to new foods,” she wrote. “It is the parents’ job to help the children take small steps to confront the issue.”

It is often helpful to offer rewards, Dahlsgaard continued. She cited things like time to play a video game or watch a favorite program if they have tasted a challenging food at dinner.

“Don’t indulge or entertain poor behavior: Picky eaters will whine, cry, scream, and flat-out refuse. Paying attention to these behaviors will only make them more likely to continue,” she wrote.

Zucker summed up the problem when she noted, “There’s no question that not all children go on to have chronic selective eating in adulthood. But because these children are seeing impairment in their health and well-being now, we need to start developing ways to help these parents and doctors know when and how to intervene.”

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