Jake Gyllenhaal admits that he drove himself "insane with hunger" whilst filming scenes for Nightcrawler.
Jake Gyllenhaal
The actor's co-star Riz Ahmed, who played Jake's characters sidekick Rick Carey in the film thought he was going to be eaten alive during the movie, because Jake was so hungry and living off a diet of chewing gum to lose 30lbs for the role.
He explained to the Metro newspaper: "Jake lost a lot of weight for the role, he was literally surviving off chewing gum and driving himself with hunger, which makes sense because his character is desperately hungry for success.
"He's looking at me in the film like he might want to eat me.
"There was this primal energy coming off him."
Despite the concerns, the star found working with Jake "really inspiring".
"He's someone who really pushes himself to limits," he added.
As well as chewing gum, Jake lived on a diet of kale salad and ran 15 miles each day from his home in Hollywood to the movie set.
Jake spoke recently of his fitness, saying: "I made a lot of choices physically.
"The running thing, you're pretty hungry because you're not eating a lot of food.
"You're lonely because you're not meeting your friends for dinner. People go, 'Hey you want to meet for dinner after work?' I go, 'Well, I'm shooting all night.' 'All right, you want to meet for lunch?' I'm like, 'I can't!' So I'm gonna go run."
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