More needs to be done to help young people who self-harm, a two-year inquiry into the issue has found.
One in 15 UK youngsters are thought to have self harmed
It said teachers, doctors and social workers do not receive the training they need to deal with self-harm cases, leaving many "struggling in the dark".
The inquiry, by the charitable group the Camelot Foundation and the Mental Health Foundation, found self-harmers were more likely to turn to friends.
One in 15 youngsters in the UK is thought to self-harm.
Rates of self-harm in the UK have increased over the past decade and are reported to be amongst the highest in Europe.
It accounts for around 142,000 hospital admissions every year in England and Wales, and this represents only a small proportion of the number who self-harm.
The inquiry heard evidence from more than 350 organisations and individuals concerned with young self-harmers.
The researchers also ensured they heard from affected young people themselves.
According to the inquiry's Truth Hurts report, widespread misunderstandings about self-harm often prevent vulnerable youngsters from seeking support and advice.
Adults and professionals often focus on the harming itself and can react in a judgemental way rather than trying to understand the underlying causes of the person's distress, the inquiry found.
Young people seeking help told the inquiry they wanted counselling and drop-in centres as well as self-help groups to be made available.
Chairwoman of the National Inquiry Panel Catherine McLoughlin said: "Few of us have paid attention to the growth of self-harm as a way many of them are coping with, and expressing, their distress.
"In other words, on average, in every secondary school classroom there will be two young people who have hurt themselves as a response to the pressures of growing up in an increasingly complex and challenging world."
She added that it was vital that everyone who comes into contact with young people had a basic understanding of self-harm and how to respond appropriately.
Dr Andrew McCulloch, chief executive of the Mental Health Foundation, said: "Self-harm is evidently a symptom of mental and emotional distress.
"We need to look past the behaviour and provide understanding, support and effective services for young people in the UK."
Susan Elizabeth, director of the Camelot Foundation which part-funded the inquiry, said there was an urgent need for parents, carers and friends to be given information about self-harming.
She added: "People are struggling in the dark. We must rid the fear, misunderstanding and stigma that surrounds self-harm."
The principal policy and practice officer at children's charity Barnardo's, Claire Turner, said the departments of health and education needed to work together on developing guidelines and information about good practice on dealing with the issue.
She said: "It is not just mental health professionals or GPs who need support and guidance on self-harm.
"Young people will want to talk to a trusted adult and this could be a teacher, youth worker or social worker."
Director of ChildLine services at the NSPCC Anne Houston said it heard yearly from people in great pain and distress who are self-harming.
She added: "ChildLine believes that the findings of the groundbreaking national inquiry into self-harm should provide the foundation for the provision of services, therapy or treatment that will mean young people who self-harm get the support and help they need to end their damaging and often dangerous cycle of behaviour."