A lack of safety at school could lead to childhood obesity, according to a recent study from the University of Montreal and its affiliated Research Centre at CHU Sainte Justine children's hospital.

"Childhood obesity is caused and sustained by a complex range of factors. Our research reveals a complex intertwining of feelings of being unsafe and poverty with obesity," Dr. Tracie Barnett, senior author of the study, said in a statement. "Surprisingly, we have found that although victimization at school is linked to childhood obesity and more screen-time, screen-time itself was not correlated with obesity. This suggests a key role for feeling unsafe and victimization in perpetuating obesity."

For the study, researchers collected and analyzed data from more than 1,000 Quebec youths who had just entered secondary school. The students were asked about their feelings of safety at school and whether they had been verbally, socially or physically bullied.

This information was supplemented with data covering their family background and their health behaviors. In addition, teachers rated what the atmosphere was like at their school - whether there were areas the youth were afraid to go to, for example.

"Youth who experienced chronic poverty were more likely to be overweight than those who hadn't, yet these youth tended to have higher levels of physical activity, possibly due to lesser use of car transport," said researcher Dr. Caroline Fitzpatrick. "Other factors such as feeling unsafe and being victimized at school helped explain underprivileged youths' increased probability of being obese or overweight."

The team also found that boys were more at risk of feeling unsafe and being victimized at school than girls.

The findings are detailed in the American Journal of Epidemiology.