Kelly Clarkson, a fierce proponent of body acceptance, has spent years advocating for loving the skin you're in. But her confidence in her shape hasn't always been apparent, and she told Attitude in a new interview that working tooth and nail in the early stages of her career to stay thin was a maddening and depressing ordeal.

“When I was really skinny, I wanted to kill myself. I was miserable, like inside and out, for four years of my life,” she said. “But no one cared, because aesthetically you make sense. It was a very dark time for me. I thought the only way out was quitting. I like wrecked my knees and my feet because all I would do is put in headphones and run. I was at the gym all the time."

Clarkson said third album My December, the entirety of which she co-wrote and co-produced before its 2007 release, marked a critical turning point in her career that found her taking control of her life and creative efforts. And one particular song — a fan-favorite — signaled the switch.

"There's a song on My December called 'Sober.' There's this line 'picked the weeds but kept the flowers' and I just live my life by that because you are who you surround yourself with," she said. "I was around some really negative people, and I got out of it because I had a lot of great people there, too. It was a case of turning around, facing them and walking toward the light."

Now, listening back to some of her old material, Clarkson said she can hear her former self screaming out for help.

“I listened to all these songs for the last 15 years, you can tell there’s a suppressed individual in there. It’s very liberating to work in an environment that’s healthy,” she said.

Clarkson's Meaning of Life, her eighth studio album, is due out Friday (October 27).

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