When a performer is asked to drop weight for a movie role, it's typically a woman -- but not always. In fact, Jason Segel recently said he was "forced" to slim down for 'The Five-Year Engagement,' which opens this weekend.

On Monday's 'Late Show with David Letterman,' Segel said he'd lost 35 pounds, explaining, "I was forced to lose weight for this movie ... I was told that it had to be conceivable that [co-star] Emily Blunt would ever choose me to be her husband. Which is fair."

Who issued the edict? Segel said it was "the studio president," which seemed to indicate he meant Ron Meyer, the president of Universal Pictures. And the studio was serious -- Segel said he was assigned a trainer who put him through twice-daily workouts and watched what the actor ate.

But where there's a will to cheat on a diet, there's a way -- even in plain sight.

"What they didn't anticipate is that I'm very clever," he told Letterman. "I play a chef in the movie. So there are a lot of scenes where I have to eat. I would pay my co-stars nominal amounts of money to mess up their lines during the scenes so I would get to keep eating."

Watch Segel talk to Dave below.

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