People with fewer than five A to C GCSEs are more likely to self-harm than students with good results, a charity is warning.
The Prince's Trust surveyed 2,161, 16 to 25-year-olds and one in five said they did things like cut or burn themselves.
For people with poor GCSE results, that jumped to nearly one in three.
Stacy Hawkins, 22, said her mental health problems started when she moved to a new school in Cornwall aged 15.
"I was bullied," she said. "I didn't fit in.
"I'd be pushed, shoved, tripped up in the corridor and I couldn't really concentrate because I was thinking more about what was going to happen once I'd left class knowing I'd probably be beaten up again."
In the end Stacy didn't get any GCSEs at grade A to C.
That meant she was unable to go to college, which is one of the reasons she says she ended up leaving home at 17.
It was shortly after that when she started self-harming.
"I'd cut myself," she revealed. "I'd burn myself, I'd try and break my bones. I'd take large overdoses.
"I don't really know why I did it. It just made me feel better. It helped me release some of that anger and that if the world was hurting me why shouldn't I hurt myself?
"It seemed as though life really wasn't worth living."
Paul Brown works for The Prince's Trust and says people like Stacy need more help from the government, charities and the private sector.
"We believe more needs to be done in school, with schools working together with organisations like The Prince's Trust, to provide specialist support to those young people who need help to overcome the issues in their lives," he said.
"We need to redouble our efforts and make sure we focus on the most vulnerable young people.
"That includes those who've left school with fewer than five good GCSEs because we know they're more likely to suffer a whole range of mental health issues."
One person the charity has already helped is Stacy.
"I'm in a lot better place now, I rarely self-harm," she said.
"I feel more confident about talking to people about how I feel.
"I've gone back to college to try and better my English GCSE and I'm generally feeling a lot better in myself."
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