Frank Bruno revealed he has been sectioned for mental illness twice in the past 18 months.
Bruno, a British boxing favourite who used to be the world heavyweight champion, made the admission in a video address at the Liberal Democrat party conference.
Revealing mental illness is a problem he still struggles with since first being sectioned in 2003, Bruno said he supported reform of the care system being carried out by minister Norman Lamb.
Bruno's battle with the illness came to light when he taken to a psychiatric hospital in a convoy of three police cars.
"My name is Frank Bruno and I'm talking from experience of being sectioned about three times, two times in the last 18 months," he said.
"I'm just a nobody really, I'm just a human being. Yesterday I used to do boxing and I used to be a celebrity but I'm talking to you as a human being from experience.
"I met Norman Lamb and he's changed a lot of different things for mental health people. He's very concerned; very, very passionate."
The Lib Dems' final conference before the next general election ends on Wednesday 8 October.