Matt Damon not so sexy in '08

We told you back in December that PEOPLE magazine's 2007 Sexiest Man Alive would plump up for a role in the upcoming thriller The Informant. Sure enough, six months later, Matt Damon is, yes, plump.

Damon estimates that he's put on 20 to 30 pounds -- not to look fat, really, but to look "doughy," he says. Mission accomplished.

How did the Oscar-winner pack on the pounds? Well, he did just what we preach here at That's Fit not to do. He stopped working out and basically ate whatever he wanted.

"I ate a lot of In-N-Out, a lot of burgers, a lot of beer and basically had a great time," he said. A great time it may have been but I bet in no time, this guy will be back in fighting shape, looking more like the photos featured in the gallery below.

More on Damon's expanding waistline in the Bodywatch section of this week's PEOPLE, on newsstands today.