New reports reveal that Jake Gyllenhaal dropped 30 pounds for his role in his new movie, 'Nightcrawler', which hit theaters on October 31.

The 33-year-old American actor portrayed the role of Lou Bloom, a career-hungry young man who shoots gory footage for a Los Angeles' based publication.

In the movie, Gyllenhaal is leaner and slimmer compared to his usual buff appearance since he intentionally lost 30 pounds from his 180-pound frame, Business Insider reported.

"I would try to eat as few calories as possible. I knew if I was hungry that I was in the right spot. Physically, it showed itself, but chemically and mentally, I think it was even a more fascinating journey. It became a struggle for me," he told Variety.

Riz Ahmed, Gyllenhaal's co-star in the movie, said that Gyllenhaal had a bowl of luxury chewing gums that were elaborately flavored to trick his brain into thinking that he was having a meal.

The actor was on his exercise bike having chewing gum and almond tea with one calorie, said Ahmed at the Toronto Film Festival this week.

Gyllenhaal was sometimes sour during the shooting since he was hungry and hadn't eaten, but he was aware and apologetic about it, Ahmed said.

On some shooting nights, the actor would not eat all or he would only have small bites of meat, crackers, or kale salad and run 15 miles from his house to the film's set, according to Variety.

Gyllenhaal is not only the star of 'Nightcrawler', but he is also the producer of the film. He worked with Dan Gilroy, a screenwriter and first-time director, for three months, brainstorming for the pre-production, according to Business Insider.

The movie is an independent and R-rated film which has already raked in over $11 million at the box office after hitting the theaters.