John Goodman

John Goodman showed off his significantly trimmer body on CBS' Late Night with David Letterman this week, telling the host his weight loss is going to be "an ongoing process for the rest of my life."

Check out photos of Goodman through the years

The 57-year-old actor, widely known for his role in the popular sitcom Roseanne, told Letterman on Wednesday that, at his heaviest weight, he was pushing 400 pounds.

"I'd get off of Roseanne — every spring. I'd lose 60 pounds every spring. And then I got too fond of the barley corn," he said. Then he'd gain it all back -- "and some."

Goodman, who's part of the ensemble in HBO's Treme, is keeping his weight-loss goals in perspective. "I'm not going to look like Paris Hilton or anything like that," he joked.

Check out the clip: