Singer and actress Billie Piper has said her early experiences of being famous and living an independent life made her "cynical" and "jaded".
She told the Changes With Annie Macmanus podcast she found being in the public eye as a teenager a tiring experience.
She said she has never worked as hard as she did when she first found fame as a musician.
"It was the most punishing schedule ever," she said. "I think it would rival any sort of businessman."
Piper moved away from home before she was 18 as her music career took off, with hits including Because We Want To.
"I think I saw a lot of things at a very young age, and I think some of that can be really good and informative and it means you see parts of life that you wouldn't normally see, maybe ever," she said.
"Then in other ways, I would say it made me quite cynical, quite jaded and very reclusive and incredibly paranoid.
"These are the sort of negative changes and things that arguably sort of affected my personality for the rest of my life... things that I've tried to deal with since."
Piper said that by the time she became an adult she was "so angry and so exhausted and burnt out".
She added: "And there was this real streak of rebellion, it was a bit like 'f*** you' to everyone, and I felt quite uncompromising about that in a way that is a certain type of late teen, early-20s energy that can carry on.
"But I also had met and been in a relationship with Chris Evans at that age, and he was someone who knew the industry, who knew the world, who knew how important it was for me to have some semblance of normal life."