Julia Hartley-Brewer has said she "deliberately drank too much" at 14 but didn't consider it "self harm" after a study found that one in four 14-year-olds were self-harming.
It comes as ministers have been urged to address the "crisis in children's mental health" after a Children's Society report was published.
The charity's annual Good Childhood Report, which examines the state of children's well-being in the UK, found that out of the 11,000 children surveyed one in six reported self-harming at 14.
Based on these figures, the Children's Society estimates that nearly 110,000 children aged 14 may have self-harmed across the UK during the same 12-month period, including 76,000 girls and 33,000 boys.
One young person told the charity: "I felt like self-harming was what I wanted to do and had to do as there was nothing else I could do. I think there is help for young people but not the right kind of help.
"Feeling not pretty enough or good enough as other girls did contribute towards my self-harming, however, I don't feel just being a girl is the reason as I think boys feel the same way too."
Almost half of 14-year-olds who said they had been attracted to people of the same gender or both genders said they had self-harmed (46%), analysis revealed.
'I deliberately drank too much at 14 and I wasn't self-harming'
Talking to Julia Hartley-Brewer on talkRADIO Lucy Capron from The Children’s Society said the organisation "deliberately" asked the children what they defined as self-harm, which Hartley-Brewer challenged.
"I don’t believe that it was the case that one in four girls in my school were self-harming and they were all keeping it quiet. This is either growing massively or there is an over-reporting of this and my worry there is a combination of the two," said Hartley-Brewer.
"When you talk about self-harming I think most of will think about kids cutting themselves, cutting their thighs which is very common because it is easily hidden, what other types of self-harm are we talking about?"
"What the Children’s Society did, was we deliberately left it up to young people to identify what they meant as self-harm, so the question that was asked of young people was, 'have you deliberaly hurt yourself'," said Capron.
"As far as I can tell that could be deliberately drink too much, taking drugs and the like, I’ve got to be honest with you, I deliberately drank too much when I was 14 and I don’t think I was self-harming," argued Hartley-Brewer.
"Well, I think in that case, you would’ve potentially answered no to that question because you wouldn’t defined that as self-harm," countered Capron. "What he Children’s Society is most concerned about, for that amount of children to answer yes to that question, is a growing issue."
The Children's Society advises anyone contemplating self-harm to talk to someone they trust. Image: Pexels
Capron has suggested young people speak to an adult they “trust” or to seek ‘professional help’ if they’re contemplating self-harming.
“We would always say that everyone suffering from mental health - or certainly thinking about self-harming in anyway - should speak to an adult they trust and get professional help,” she said.
Julia asked if some young people are self-harming as a way to add something ‘interesting’ or give them an ‘identity’ to their personality.
'Talking about mental health is a positive thing'
“I don’t think we would say that people are trying to kind of have mental health issues to have something interesting about their lives, and it’s not something we’ve seen within our services,” added Capron.
“I think talking about mental health is a really positive thing.
“We want more people to not be able to bottle up these issues and a lot of young people say that they would start self-harming as a mechanism of coping and in some cases that can make them feel happier initially because they’ve taken some control of their live, but what it does mean is that it’s not a long-term sustainable healthy coping mechanism.”
Children's Society chief executive Matthew Reed said: "It is deeply worrying that so many children are unhappy to the extent that they are self-harming.
"Worries about how they look are a big issue, especially for girls, but this report shows other factors such as how they feel about their sexuality and gender stereotypes may be linked to their unhappiness."
If you've been affected by any of the issues mentioned, you can contact Childline on 0800 1111 or Samaritans on 116 123.