Psychologist Professor Tanya Byron says so much is expected of today's schoolchildren but they don't have the 'emotional resilience' to cope with failure.
Speaking at the Cheltenham Literary Festival, Prof Byron said a 'highly targeted, focused, pressured, academic system' had led to teenagers presenting to psychologists with anxiety disorders.
She said young people in aspirational families are increasingly suffering what she likened to 'executive stress burnout'.
And she criticised the 'third world' mental health system offered to teenagers.
She said half of all adults suffering mental illness had begun showing signs as a teenagers, but that only six per cent of funding was allocated to them.
The leading author and broadcaster said problems had been created by a 'risk-averse culture', with children afforded fewer 'developmental freedoms' as their parents generation.
She said: "I think that has a massive impact on children.
"Where I see that clinically is in the significant number of children now presenting with anxiety disorders.
"It's this sense of a lack of an ability to build an emotional resilience for life.
"This in an interesting phenomenon that's quite new, where we're seeing a growing number of young people presenting to clinical services who have traditionally would not have presented.
"What we're seeing now is children and young people coming from backgrounds where there are a huge number of what would traditionally be seen as protective factors, but these children are struggling to cope.
"When they transition through adolescence, that's when you see them falling apart."
She added: "These are children from aspirational families who are in a world that's created like a bubble around them.
"A highly targeted, focused, pressured, academic system where I'm seeing 14, 15, 16-year-olds presenting with what looks like executive stress burn out.
"We're seeing young people who don't know how to fail. Risk taking isn't allowed - if we fail then we are a failure.
"So for me it fits more around emotional resilience and the opportunity for young people to develop that."
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