Demi Lovato has revealed that she was within '5 to 10 minutes' of dying in a trailer for her new YouTube documentary.

The 28-year-old has battled alcohol and drug addiction for more than a decade and in 2018 she suffered a serious overdose that saw her rushed to hospital in Los Angeles.

"I had three strokes," Lovato says in the trailer for Demi Lovato: Dancing With the Devil. "I had a heart attack. My doctors said that I had five to 10 more minutes [to live]."

She adds: "I've had so much to say over the past two years wanting to set the record straight about what it was that happened.

"I've had a lot of lives. Like my cat, you know? I'm on my ninth life."

Watch the full trailer for the four-part series, which is released on March 23, below: