Oct 08, 2014 05:15 PM EDT By J Baulkman, UniversityHerald Reporter

Children who are difficult eaters may have underlying psychological issues, according to a recent study.

Researchers from the University of Montreal found that restrictive behaviors can appear before puberty. Their findings raise questions about the way eating disorders develop and are diagnosed.

"Many researchers believe that bulimia only appears at adolescence, but our studies indicate that the problem can arises much earlier," said clinical psychologist and Professor Dominique Meilleur, who led the study. "It is possible that it is currently under-diagnosed due to a lack of awareness and investigation."

For the study, Meilleur and her colleagues studied the psychological, socio-demographic and physiological characteristics of more than 200 8- to 12-year-olds with eating problems. Kids with physical issues that could cause eating problems, such as diabetes or cystic fibrosis, were excluded from the study.

They found that the children often suffered from other problems: in particular, anxiety and mood disorders and attention deficiency. More than 15.5 percent of the children involved in the study made themselves vomit occasionally and 13.3 percent presented bulimic behaviors.

"These results are very concerning but they may help clinicians reach a diagnosis earlier by enabling them to investigate these aspects," Meilleur said.

Across the study, 52 percent of the children had been hospitalized at least once due to their eating problem and 48 percent had been treated as outpatients emergency responders. The results of this study indicate that 22.7 percent of the children identify having been mocked or insulted for his or her appearance as a trigger event to the modification of their behaviors.

"Many factors are associated with the development and persistence of eating disorders," Meilleur explained. "For some children, bullying can initiate or reinforce boy image preoccupations and possibly lead to a change in eating behavior."

The findings were presented at the Eating Disorders Association of Canada conference in Vancouver.

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