TORONTO - As a teen, Peter Czerwinski was fighting for his life in a Toronto hospital because he refused to eat food. These days, he gets his kicks gorging on it.

Czerwinski, 24, a former anorexic from Mississauga, Ont., is now a competitive eater with over two-dozen championship trophies for stuffing his face with everything from heaps of chicken wings to corned beef and watermelon.

His ironic life path is outlined in "The Story of Furious Pete," which is screening at the Hot Docs film festival.

"That was the worst time in my life," Czerwinski said in an interview of the eating disorder that nearly killed him at age 16.

"I know how many (people) I actually did hurt, like, both emotionally and physically, and those are just years of my life that I'll never get back. So it's tough looking back on those times but it made me the person I am today. Overall, in a way I'm kind of glad it did happen because I became stronger, mentally, and I'm able to approach any task now with confidence."

Czerwinski suffered from anorexia for about a year in 2002 and spent another three years recovering from it. It was in 2007, when he was getting into bodybuilding, that he went to a restaurant and discovered his ability to gobble.

"One of my buddies, he likes to really challenge people to do crazy, random things and we went into this breakfast place and there was this big platter of breakfast food (on the menu)," recalled Czerwinski, who is working on his master's degree in mechanical engineering at McMaster University.

"He asked the waitress what the record was for the amount of plates eaten and it was two in an hour, and I somehow ate four.

"And then I just realized that my brain never tells me I'm full."

As Czerwinski took on more eating stunts, he videotaped himself and put the clips on YouTube, where they went viral. He also entered eating contests, tackling just about any dish on offer, except those with mayonnaise, which turns his stomach.

"You have to see him in action -- it's scary," said George Tsioutsioulas, the Toronto-based filmmaker who first saw Czerwinski in action at a burger-eating contest in Delaware.

"I remember right before he started it, it's almost like he became a different person. He said, 'OK, stand back.' I don't know if that was a warning, like if I was going to lose a finger if I got too close or he was going to push me away, but he was definitely in the zone."

The doc captures Czerwinski at contests throughout Canada, the United States and Germany, and the footage isn't always easy to watch.

"Oh, you'll want to leave the theatre but you won't," Czerwinski said of one scene where he pigs out on 15 pounds of ribs. "It's pretty gross."

For all his gluttony, Czerwinski appears to be in top shape, and says he trains "very very hard" at the gym and tries to maintain a healthy diet.

Still, how does he recover from these contests?

"The morning after? Not fun," he said.

"You don't want to know," added Tsioutsioulas. "You don't want to go into the bathroom afterwards. Stay clear."