It has been estimated that 10% of young people in Britain have self-harmed. There are no official figures, but hospital records show that nearly 500 adolescents a week are treated for deliberately injuring themselves. Emma Parsons, producer of Born Survivors: Cut Up Kids, reveals why one woman resorted to self-harm.
Tor is a country girl who grew up surrounded by ponies and public school life. She had a normal childhood, with a normal family.
Tuesday 18 December
10.30pm, BBC Three
But mounting pressure to achieve the entry grades for an exclusive sixth form college caused her to crack, and self-harm became a large part of her life.
"You just take a knife," says Tor. "You just press it down on your skin and you just pull it. You end up bleeding.
"When you drag the blade across your skin it just feels a release.
"It's like when you hold your breath, hold your breath. You just feel you are going to blow up. Self-harm is like when you breathe again."
Her problems began whilst preparing for her GCSEs at the age of 15. She felt a large amount of pressure to do well in her exams and her parents sent her to a crammer college in Oxford.
I'd never known or heard of anyone self-harming so it didn't occur to me that that's what it was
She and her school had high expectations that she would get excellent grades.
As a way of coping with the pressure, she and her friend carved hearts into their arms with a pair of compasses.
"I think this is when it occurred to me that this could be a way of helping myself and letting the pain inside disappear," she explains. "It was a kind of release".
"I'd never known or heard of anyone self-harming so it didn't occur to me that that's what it was."
She would hurt herself at most once or twice a week in private in the school toilets.
Tor's best friend Gary understands self-harm as he also cuts himself
She moved on from using compasses to pencil sharpener blades and scalpels taken from the art room. She only cut on the tops of her arms to ensure that no one would see. For Tor, self-harm was private.
"It's not fashion, it's not attention seeking, it's not about being cool or hard.
"It's very secret, it's a secret thing.
By sixth form the school and Tor's parents had started to guess something was wrong. Tor was no longer achieving academically. She was often angry and would punch the school walls as a way of hurting her self.
"Because they are all bumpy, if you punched them hard enough you end up cutting your knuckles," she said.
The self-harm was still a secret, even as her family tried to help her. She saw a doctor and was diagnosed with depression.
By the age of 20, Tor had dropped out of agricultural college and was homeless. She found herself in Southampton and after living in a few homeless shelters was given a bedsit in a Southampton housing project run by the YMCA. It was here that her self-harm reached its peak.
She was self-harming on a daily basis. She bought a set of kitchen knives and would also use cigarettes and lighters to burn herself.
In a single year, she was treated in hospital on over 30 occasions.
She first began to turn her life round when she was given support by a Community Psychiatric Nurse who taught her different coping strategies.
She also joined Safe House, a drop-in centre for vulnerable young people in Southampton.
"Since being in Southampton I've not had to hide what I'm feeling; I can just be myself.
"When you've had to hide everything, you kind of don't learn everything and grow up as you should.
"You kind of have to re-start that over again. It's kind of what it felt like coming down to Southampton - just restarting being a teenager and going through it all again."
After nine years of self-harming and now aged 24, Tor has found a career she loves and hopes she can move forward with her life.
She was offered the chance to learn to sail and the experience had a dramatic effect on her. She now hopes to pursue sailing professionally.
"I think sailing has really helped. Just thinking about it or doing it has been a great distraction technique for me and has taken my mind off self-harming all together."
"It's been tough but it's been worth it 'cause now I've found something I really want to do.
"If it wasn't for sailing I might be back where I was."
Tor's story features in the BBC Three documentary Born Survivors: Cut Up Kids which will be broadcast at 10.30pm on Tuesday, 18 December.