Bullying in childhood pushes some teens to self-harm, and parents and teachers may be unaware.

After studying nearly 5,000 children and teens, researchers from the United Kingdom found that being bullied during childhood increases the risk of self-harm later in life, not just because bullying victims are prone to depression, but also because bullying exacerbates already risky situations.

Earlier this year, a 13-year-old boy hanged himself after reportedly being bullied in school. Coupled with the rise of cyber bullying and sexual assault documented on social media platforms, bullying for children and teens is becoming less about building character and more about sheer survival.

“A common perception is that those who self-harm do this because they are depressed or mentally ill. We found that being bullied, in particular chronically in primary school, directly increases the risk of self-harm,” said study author Dieter Wolke, PhD, a professor of psychology at the University of Warwick in England.

The difference is that self-harm caused by bullying is different from, and not necessarily reliant upon, feelings of depression, though being bullied also increases a child’s risk of developing depression, the study authors wrote.

This means that children who don’t show overt signs of depression but may be self-harming can be missed by parents, teachers, and doctors.

In the United States, 14 to 17 percent of adolescents and young adults self-harm, according to a study published in the Journal of Youth and Adolescence. Self-harm behaviors include cutting or burning the skin and swallowing pills, and they are often used to release tension or communicate stress.

“Self-harm is used to release stress and to feel relief, at least for a short while,” Wolke told Healthline.

What Is Bullying?

In this study, bullying was classified as repeated aggression—at least once a week—that was conducted with the intention of harming another and was sustained over a six-month period, either online or in person.

“Bullying is not normal conflict,” Wolke says. It’s more than an independent fight or a single instance of abuse. “All children exposed to bullying had increased risk, but those bullied over years had the highest risk of using self-harm.”

Even the President is taking action to show Americans that bullying can have serious ramifications.

“If there’s one goal of this conference, it’s to dispel the myth that bullying is just a harmless rite of passage or an inevitable part of growing up,” President Obama said at a 2011 White House conference. “It’s not.”

In Wolke’s study, 4,810 children from the Avon Longitudinal Study of Parents and Children (ALSPAC) in the United Kingdom answered a self-harm questionnaire at the age of 16 or 17. Researchers compared those answers with childhood bullying reports from children, parents, and teachers collected at ages 8 and 10.

Nearly 19 percent of participants reported self-harming at any point, and 16.5 percent reported repeatedly self-harming. Sixty-six percent of those who self-harmed reported being the victims of bullying. Wolke and his team theorize that if bullying hadn’t occurred, 20 percent of the self-harm cases could have been prevented.

“We show that [bullying] has serious consequences years later and should not further be belittled or ignored,” Wolke said.

Bullying often goes unnoticed, and as many as 40 percent of children believe neither their teachers nor their parents can do anything to help.

“It is also shameful or seen as a failure by the children—disclosing makes them feel even more worthless,” Wolke said. “Disclosure is the first step to help and children need an atmosphere at school, home, or towards others to be able to talk about it. Talking through potential ways of dealing and coping is a first step toward avoid long-term adverse effects.”