Hemsworth is filming for Ron Howard's "Heart of the Sea," where he plays a much lighter character. The film is based on the true events that inspired Herman Melville to write "Moby Dick."
The 30-year-old Australian actor nearly starved himself to drop his superhero weight. "We had to get rather skinny," he said. "We're on about five or six hundred calories a day."
To put that in perspective, it's about one Big Mac or just two Snickers. Making matters worse, Hemsworth regularly fasts for 15 hours straight.
Don't worry, ladies. The Aussie hunk won't be a frail for long. He still has "The Avengers: Age of Ultron" to bring back his Thor brawn. Unfortunately, it's not due out in theaters until May 2015.