Children bullied during their early years are up to three times more likely to self harm than their class-mates when they reach adolescence, a study has revealed.
According to its findings, around half of 12-year-olds who subject themselves to deliberate injury were frequently picked on.
The research also showed victimised children with mental health difficulties and those from troubled families were at greater risk of resorting to destructive behaviour which could have serious long-term effects in later life.
The study's authors have now called for more effective programmes to prevent bullying in schools.
In a paper, published by the British Medical Journal, they suggest efforts should focus on improving the ways in which
children cope with emotional distress.
"Bullying by peers is a major problem during the early school years," they said.
"This study found that before 12 years of age a small proportion of children frequently exposed to this form of victimisation already deliberately harmed themselves and in some cases attempted to take their own lives.
"Frequent victimisation by peers increased the risk of self harm,"
The researchers also raised fears over the long-term implications of bullying which, they said, could result in psychological issues, serious injury or death.
"This study adds to the growing literature showing that bullying during the early years of school can have extremely detrimental consequences for some children by the time they reach adolescence," they wrote.
"This finding is even more concerning given that studies have suggested that early patterns of self harm can persist through adolescence into adulthood and increase the risk of later psychological problems.
"Therefore, such maladaptive coping strategies need to be tackled in childhood and early adolescence before they become a persistent problem or lead to serious injury or death."
The authors, from King's College London, looked at more than 1,000 pairs of twins - born between 1994-1995 in England and Wales - at five, seven, 10 and 12-years-old.
The children were assessed on the risks of self-harming in the six months prior to their 12th birthdays.
Data available for 2,141 individuals showed 237 children were victims of frequent bullying and, of that number, 18 (around 8%) self harmed. This involved cutting or biting arms, pulling out clumps of hair, a child banging its head against walls or attempting suicide.
Of 1,904 children who were not bullied, 44 (2%) self harmed.
The research found marginally more girls (52%) than boys resorted to wounding themselves.
It also showed bullied children with a family member who had either attempted or committed suicide were more likely to self harm than others.
"If bullying could have been eradicated (and everything else remained the same), a sizeable proportion of the cases of self harm could potentially have been prevented," the authors concluded.
"Although only a small proportion of bullied children in this sample engaged in self harm, this is clearly too many and victims need to be provided with alternative coping strategies from a young age."
They added: "Prevention of non-suicidal self injury in young adolescents should focus on helping bullied children to cope more appropriately with their distress.
"Programmes should target children who have additional mental health problems, have a family history of attempted/completed suicide, or have been maltreated by an adult."