LOS ANGELES, CA - NOVEMBER 27: Ashton Kutcher attends a basketball game between the Indiana Pacers and the Los Angeles Lakers at Staples Center on November 27, 2012 in Los Angeles, California. (Photo by Noel Vasquez/Getty Images)
Kutcher says that he started a fruit-only diet to prepare to play the Apple co-founder for the biopic Jobs, which premiered Friday night at the Sundance Film Festival.
The diet, which the film claims Jobs adhered to, ended up sending Kutcher to the hospital with pancreas problems.
"First of all, the fruitarian diet can lead to like severe issues," Kutcher said after the film's screening. "I went to the hospital like two days before we started shooting the movie. I was doubled over in pain.
"My pancreas levels were like completely out of whack," Kutcher added. "It was really terrifying ... considering everything."
Jobs died of pancreatic cancer on Oct. 5, 2011.
The film is the first of two biopics concerning the entrepreneur's life. Aaron Sorkin is writing the screenplay for a competing project being produced by Sony Pictures.
Jobs is due in theaters in April. Josh Gad plays Apple co-founder Steve Wozniak in the film, which was directed by Joshua Michael Stern.
The story follows Jobs and Wozniak from the company's beginnings -- scenes were shot in the Palo Alto, Calif., garage where Apple was started -- to the launch of the iPod in 2001.
Kutcher, who says he studied hundreds of hours of Steve Jobs tapes, captured the man's hunched walk and demeanor in the film.
The actor and the entrepreneur had personal similarities, Kutcher said. "We both have a ravenous interest in the tech space."
Jobs had setbacks as well as tremendous success.
"He's a guy that failed and got back on the horse," said Kutcher. "I think we can all sort of relate to that in some place in our life where we are moving forward with something and we fall down. You have to have the guts to get back up and go again. I think I share that as well."
There was no falling down Friday night. The premiere was one of the most sought-after tickets at the festival.
After an ovation from the audience, Kutcher and Gad attended a party celebrating Jobs at the Sundance hotspot Nur Khan presents NK Hosts house.
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