Chris Hemsworth Ate 500 Calories a Day While Filming In the Heart of the Sea

Chris Hemsworth went on a 500-calorie-a-day diet to film In the Heart of the Sea. Credit: GTRES/FAMEFLYNET PICTURES

Women of the world who are dieting, Chris Hemsworth sympathizes with your plight. The Australian actor, 31, bulked up to get the body of a Norse god in Thor: The Dark World, but for his latest film, due out in December, he ate a meager 500-calorie-a-day diet!

Starring in Ron Howard's action-adventure flick In the Heart of the Sea, about the real-life disaster that inspired Moby Dick, Hemsworth plays first mate Owen Chase. Chase and his shipmates are attacked by a whale in the winter of 1820, and forced to survive the elements — and battle starvation — after being shipwrecked.

"We have to shoot the really skinny stuff where we drop down to 5, 6, 700 calories a day, [for] a good three or four weeks and it's going to be pretty uncomfortable, but we'll be together in our misery," Hemsworth told Entertainment Tonight of his costars Cillian Murphy, Ben Whishaw, and Paul Anderson.

Though director Howard is careful to ensure his actors do their rapid slimdowns healthily, Hemsworth told ET all he can think about is getting to the end of filming. "I spend more time thinking about food than anything else at the moment," admitted the star, who worked out twice a day and ate eight meals a day to put on 20 pounds of muscle when filming the Marvel franchise.

What's on his list of must-have cheat foods once he's in the clear on set? "All the bad stuff — pizza, hamburgers, ice cream, anything that is not on the menu — is something you have an obsession with!" he said.

In the Heart of the Sea hits theaters on Dec. 11.

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