First author Laura Bogart of Boston Children's Division of General Pediatrics and her team collected data for the study by tracking a group of 4,297 children and adolescents from fifth to 10th grade. The researchers periodically interviewed them about their mental and physical health and their experience(s) with bullying.
The study, published online in the journal Pediatrics, found bullying at any age was associated with worse mental and physical health, increased depressive symptoms and lower self-worth. However, those who experienced bullying both in the past and present showed the lowest health scores.
In addition, study participants who experienced chronic bullying also reported increased difficulties in physical activities such as walking, running or participating in sports.
"Our research shows that long-term bullying has a severe impact on a child's overall health, and that its negative effects can accumulate and get worse with time," Bogart said in a statement.
"It reinforces the notion that more bullying intervention is needed, because the sooner we stop a child from being bullied, the less likely bullying is to have a lasting, damaging effect on his or her health down the road."