Even moderate picky eating can have adverse effects on a child's health, according to a recent study CNN reported.

Researchers at Duke University found that picky eating often coincides with serious childhood issues such as depression and anxiety that may need intervention.  The habit, not surprisingly, can also result in poor nutrition for kids.

"This is not a simple story of indulgent parents or bratty kids," psychologist Nancy Zucker, lead author of the study, told Reuters. "These are children who are profoundly sensitive to their internal and external world - so things smell stronger and they may have more intense feelings."

The study revealed that more than 20 percent of children ages 2 to 6 are selective eaters. Of them, nearly 18 percent were classified as moderately picky. The remaining children, about 3 percent, were classified as severely selective -- so restrictive in their food intake that it limited their ability to eat with others.

"These are children whose eating has become so limited or selective that it's starting to cause problems," Zucker, director of the center for eating disorders at Duke University, said in a statement. "Impairment can take many different forms. It can affect the child's health, growth, social functioning, and the parent-child relationship. The child can feel like no one believes them, and parents can feel blamed for the problem."

For the study, researchers collected and analyzed data from more than 3,000 children.               .

They found that children with both moderate and severe selective eating habits showed symptoms of anxiety and other mental conditions. They also were nearly twice as likely to have increased symptoms of generalized anxiety at follow-up intervals during the study.

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

Although children with moderate picky eating did not show an increased likelihood of formal psychiatric diagnoses, children with severe selective eating were more than twice as likely to also have a diagnosis of depression.

The findings, which are detailed in the journal Pediatrics, suggest that parents are in conflict with their children regularly over food -- which does not necessarily result in the child eating -- and families and their doctors need new tools to address the problem.