Davina McCall has said she was taken to hospital after overdosing on drugs at the height of her addiction.
The TV presenter, who has previously spoken about her issues with drugs in her early 20s, said she was "so full of self-loathing" at the time and that she took a mix of drugs because she did not want to feel "normal".
According to the Sun on Sunday, McCall told an International Women's Day event: "Drugs took me to a very, very, very dark place and, one night, I overdosed.
"It was very frightening as it was a very gradual overdose.
"I'd had a cocktail of drugs, because I didn't want to feel normal.
"I was constantly trying to escape myself – I was like a piece of fruit rotting from the inside."
McCall added: "So then I thought 'Well, I'll just take a Valium', and the next thing I knew I woke up in hospital.
"At my lowest point, when I was filled with self-hatred, it was literally a case of 'get clean, or die'."
McCall said she was the person that "people who have crossed the street to avoid", and that she started taking cannabis before becoming a heroin addict.
"It ended up taking me to the darkest, darkest place," she said.
McCall, 52, whose TV career started on MTV in the 1990s before she landed a job as the host as Channel 4's dating show Streetmate, said she "empowered" herself to change her situation and that she made a decision to change herself.
She added: "And because I got clean I got the job I'd dreamed of and that changed my life forever.
"I hated myself so much. I was so full of self-loathing. I was telling myself constantly that I wasn't worth anything."
Following the drug overdose, McCall became clean within around a year with the help of Narcotics Anonymous meetings.
She became a household name in the early 2000s as the presenter of Big Brother, which started in 2000.
She remained on the show until 2010, and has also fronted programmes including game show The Million Pound Drop, winter sports reality show The Jump, ITV celebrity talent show The Masked Singer and ITV's Long Lost Family.