He may have gained 20 pounds of muscle to play superhero Thor, but Chris Hemsworth is now dropping all that weight (and more) for his role in Ron Howard's new film, "Heart of the Sea."


The 30-year-old actor stopped by "Jimmy Kimmel Live!" last night (Nov. 4) to talk about his new flick "Thor: The Dark World," but revealed he's been on a crash diet, which might explain his thin frame.


"['Heart of the Sea'] is the true events that inspired Herman Melville to write 'Moby Dick,'" Hemsworth explained to Kimmel, sharing the back story of why he needs to lose weight.


"A bunch of sailors in a whaling ship get struck by a whale, the ship sinks and they jump onto the small rafts and drift for 90 days. And basically they begin to die and eat each other ... a romantic comedy," he joked, continuing, "And we have to get rather skinny. So we're on 500 or 600 calories a day."


That's right, Thor will soon be a scrawny, weak man.


"I had a cheat meal a couple of minutes ago so I'm in a good mood. [I had] a bit of pizza. Like 10 [slices]," Hemsworth laughed, "But that's just once a week and then you feel really guilty."


Luckily for Hemsworth though, the rest of the cast has to follow the diet regimen, as well, so he has plenty of support.


"It's funny, you've never heard 15 big, burly guys playing sailors talk about their calorie-count, what they should and shouldn't eat, what their cheat meal is going to be," the actor said, admitting that his "meals" are barely enough to keep him energized.


"I mean, you can consume 600 calories in a milkshake," he explained. "So it ends up being a couple of small salads, a couple of small pieces of protein and that's kind of it and you go to bed hungry. And then you have like a fasting period of 15 hours, like you stop eating completely, and then you have little meals through the day."


Sounds pretty miserable if you ask us.



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