( CNN ) -- Matthew McConaughey lost 40 pounds for December 's `` Dallas Buyers Club , '' and Matt Damon worked out for four hours a day to get ripped for `` Elysium . '' Ashton Kutcher , meanwhile , wanted so badly to get the role of innovation icon Steve Jobs right , he put himself in the hospital . The 35-year-old actor became a fruitarian while filming Steve Jobs biopic , `` jOBS , '' in an attempt to `` understand some of his discipline , '' Kutcher explained to CNN . He picked up a book Jobs once read by Arnold Ehret called `` Mucusless Diet Healing System '' and began to eat nothing but fruit , shedding 15 to 18 pounds in the process , according to `` jOBS '' director Joshua Michael Stern . What the Jobs movie got right , and wrong . `` ( Jobs ) was a really disciplined guy in a lot of ways , around his work and his life and his relationships and his products , '' Kutcher said . `` And part of going on the diet was just to try to get an understanding of that . I did n't like it very much . It was really painful , ultimately . But it was really worth it , 'cause I think I gained a level of empathy towards that kind of discipline and focus that I do n't think I could have played the role without . '' Arriving Friday , `` jOBS '' traces Steve Jobs ' ascendance from college dropout to globally influential creator and will recount his founding of Apple along with Steve Wozniak ( played by Josh Gad ) . As one of the more tech-savvy stars in Hollywood , Kutcher was initially nervous to portray someone he calls his `` hero . '' `` I admire him , and I admire his work , '' Kutcher told CNN . `` The scariest thing for me was that I wanted ... people to see my portrayal of him and see it as a portrayal that was honoring him and being honest about some of the flaws that he had . That was really a daunting task . '' Of course , Kutcher came to the part with a genetic advantage : The actor , who also stars on CBS ' `` Two and a Half Men , '' shares a resemblance to the late Jobs , who died in October 2011 . But according to director Stern , Kutcher did n't try to rely on just his looks . `` Ashton walked into the first meeting already channeling Steve Jobs , '' he told CNN . `` He had the mannerisms ; he 'd studied hundreds of hours . He knew from that first meeting that I needed to take away evidence that he could play the part . '' Kutcher 's total immersion into the character was so complete that Stern walked away from the actor with newfound respect . `` He studied the guy ; he lived in his skin every day , which was n't the easiest place to live , and I really respect him quite a bit . He gave everything he had , and more than anything I knew that this role was important to him . And when something 's important to you no matter what you do , you 're going to give it everything you have . '' Despite those efforts , `` jOBS '' has faced criticism ahead of its release date , from Kutcher 's casting on down . The biopic was originally slated to bow in April , but was bumped back to August reportedly so the studio could have a longer marketing push . Reviews , thus far , have been mixed , and then there are those questioning its timing . Kutcher says that when he received the script , which was already a work in progress when Jobs died , that he did have that `` immediate concern . '' `` I know that there were some people that were close to him who did n't want a movie to be made this soon , '' he said , but because `` I have friends that actually know him , I felt ... I could at least protect his legacy somewhat by playing ( the part ) , and I knew I would dedicate myself to making it as good as I could . '' When you make as great of an impact on the world as Steve Jobs did , that story 's going to be told eventually , no matter what . `` I would rather have it get told before the tales about him get too tall and while we could tell an honest story , '' Kutcher continued . `` A lot of times , someone passes away and all of a sudden the stories become these fictional tellings of what happened . I think this film is as close to true as we could find . '' At this year 's Teen Choice Awards , Kutcher addressed the young crowd in a Jobs-ian motivational moment . He told fans `` sexy is smart , '' `` opportunities look a whole lot like work '' and closed his speech by saying , `` build a life ; do n't live one . '' CNN 's Carolyn Sung and Jane Caffrey contributed to this report .
Ashton Smith is playing Steve Jobs in this weekend 's production ' . ' The actor committed himself to the role , learning Jobs ' mannerisms and his diet . The latter aspect of the role put him in the hospital . He thought it was worth it to learn how disciplined Jobs was .