'The Informant!': Why Carbo-Loading Might Hand Matt Damon an Oscar

Matt Damon is receiving some of the best reviews of his career for Steven Soderbergh's The Informant! and he deserves all the praise. Damon plays real-life FBI whistleblower Mark Whitacre, who tries to expose his company's price-fixing tactics, only to later discover that his own tactics are under investigation. It's not just that Damon embodies his character's nerdy, jittery disposition, he also embodies his character's doughy body. Damon put on 30 pounds for the role. "I started eating like crazy and drinking dark beer," Damon told Entertainment Weekly. "Between meals on set, I'd eat a no. 1 value meal at McDonald's and then Doritos on top of it. It was absolute heaven." It might even get better, Mr. Damon. You'll probably land an Oscar nomination for this performance.

If you're a famous actor, gaining or losing weight is for a role is a surefire method to land critical props—and Academy Awards. (It's a different story if you're not famous, as Damon can tell you when everybody ignored his gaunt appearance in Courage Under Fire.) Robert DeNiro might have launched the celebrity weight wars when he packed on 60 pounds for Raging Bull in 1980. Ever since then, actors have been eating up─and eating for—these chunky parts. Renée Zellweger feasted on chocolate, spaghetti, and pizza to gain 20 pounds for Bridget Jones's Diary (reward: Oscar nomination). Charlize Theron scarfed down Krispy Kreme doughnuts for Monster (Oscar win). Anne Hathaway unwrapped a few extra Twinkies to lose her lean look in Rachel Getting Married (Oscar nomination). Even George Clooney in Syriana (Oscar win) fattened up and Tom Hanks binged before he wasted away in Cast Away (Oscar nomination).

This all sounds delicious, but to an extent, it might be more of a work requirement. In this era of Perez Hilton and camera phones, actors are always celebrities first and actors second. We see them buy groceries and park their cars and carry around their exotically named babies. The only way to really disappear in a role is to stop looking like yourself. When Damon appears 30 pounds heavier in The Informant, we hardly recognize him as Matt Damon anymore—at least not the Matt Damon we all know: 's Sexiest Man Alive, Ben Affleck's BFF, Sarah Silverman's imaginary boyfriend. He transforms into his character right before our eyes.

There's just one job hazard. Sometimes—especially if you're female—the extra pounds become extra baggage in your regular life. After Bridget Jones, reporters wouldn't stop asking Zellweger questions about her weight. When she gained a few pounds to play the author Beatrix Potter in Miss Potter, it was as if she was trying to keep it a secret, like her onscreen weight gain was a personal vice. " I don't want to talk about it," she said in a interview. "Otherwise, I'm going to talk about my weight every single day for the rest of my life."

What do you think?!? Click here to see our gallery of the phat-est fat performances on the big screen.