Nearly half of unemployed young people are "always" or "often" depressed, while more than a quarter are depressed regardless of employment, the Prince of Wales' charity has revealed.
The Prince's Youth Trust research on the happiness of young people found 27% in work reported feeling down or depressed "always" or "often" increasing to 48% amongst those who are not in employment, education or training (Neets).
The survey findings, based on interviews with 2,136 16-to-25-year-olds in the UK, showed that one in 10 feels unable to cope with day-to-day life with those classified as Neets twice as likely to feel this way as their peers.
The trust's fifth annual Youth Index gauged young people's happiness across a range of areas from family life to physical and mental health.
More than one in five, or 22%, said they did not have someone to talk to about their problems while they were growing up, with Neets significantly less likely to have had someone to confide in.
Martina Milburn, chief executive of The Prince's Trust, said: "A frightening number of unemployed young people feel unable to cope - and it is particularly tough for those who don't have a support network in place.
"We know at The Prince's Trust that it is often those from the most vulnerable backgrounds who end up furthest from the job market.
"Life can become a demoralising downward spiral - from a challenging childhood into life as a jobless adult. But, with the right support, we can help get these lives on track."
Richard Parish, chief executive of the Royal Society of Public Health, said the recession has eroded young people's confidence and ambitions.
"The Youth Index clearly shows a worrying discrepancy between young people who are in work and those who are not," he said.
"These unemployed young people need support to regain their self-worth and, ultimately, get them back in the workplace.
"With recent record-breaking youth unemployment - the work of charities like The Prince's Trust with vulnerable young people is more critical than ever."
The Prince's Trust, founded by the Prince of Wales in 1976, helps young people into jobs through measures such as personal development programmes and mentoring. The charity launched extra help for young people with mental health needs on its team programme four years ago.
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