London: Children who are bullied in primary and secondary school are nearly twice as likely to be overweight at the age of 18 than non-bullied children, finds a study.
In the study, published in Psychosomatic Medicine, the researchers examined whether bullying in a modern context would have similar effects on weight, given that it may take different forms like cyber bullying than it did earlier.
The researchers analysed data on more than 2,000 children and assessed bullying victimisation in primary school and early secondary school through interviews with mothers and children at repeated assessments at the ages of seven, 10 and 12.
They found that 28 per cent of children in the study had been bullied in either primary school or secondary school (defined as transitory bullying), and 13 per cent had been bullied at both primary and secondary school (defined as chronic bullying).
Children who were chronically bullied in school were 1.7 times more likely to be overweight as young adults than non-bullied children (29 per cent prevalence compared to 20 per cent). Bullied children also had a higher BMI and waist-hip ratio at the age of 18.
These associations were independent of other environmental risk factors (including socioeconomic status, food insecurity in the home, child maltreatment, low IQ and poor mental health).
In addition, and for the first time, analysis showed that children who were chronically bullied became overweight independent of their genetic risk of being overweight.
"Our study shows that bullied children are more likely to be overweight as young adults, and that they become overweight independent of their genetic liability and after experiencing victimisation," said Andrea Danese, researcher at the King's College London.