Seth Rogen: From Schlub to Stud!

Seth Rogen really wowed fans at the Oscars when he debuted his svelte new look, appearing trim and dapper on the red carpet.

The Knocked Up star, 26,who shed approximately 30 pounds on celebrity trainer Harley Pasternak’s 5-Factor Diet to play the title role in The Green Hornet, has been on the keep-fit regime for nine months.

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But will the slimmed-down star change his ways permanently?

“I lost for a role, but I don’t know if I’ll keep it,” Seth says. “That’s the big question. I have a lot of tantrums. I want my food. I cry for no reason.”