For some actors, getting into character means just a few hours in hair and makeup, but others take the transformation to another level.
Matthew McConaughey is the latest star to lose weight for a role. He plays an HIV patient in the upcoming film "The Dallas Buyer's Club," and he's committed to dropping 30 pounds from his normal weight for the role.
"I'm doing this on purpose," McConaughey told Larry King about his slimmed-down appearance, adding, "I should not look healthy by the time I'm doing that film."
But McConaughey isn't the only one to go to extremes when it comes to losing weight for a role. From Christian Bale and Matt Damon to Natalie Portman and Jennifer Hudson, some stars have shed some serious weight to slim down for projects.
Check out other stars who lost weight for movie roles below:
Matthew McConaughey committed to losing 30 pounds to play a man with HIV in "The Dallas Buyer's Club," <a href="http://www.youtube.com/watch?v=pm4BsOsgek4" target="_hplink">telling Larry King</a>, "I should not look healthy by the time I'm doing that film."
Anne Hathaway not only chopped off her brown locks to portray Fantine in "Les Miserables," she lost a substantial amount of weight for the role. Though rumors ran rampant that she was starving herself, her rep claims <a href="http://www.huffingtonpost.com/2012/03/30/anne-hathaway-crash-diet-500-calorie-diet_n_1391976.html" target="_hplink">she was "on a special diet"</a> to "look more frail as she is playing a prostitute who is dying of tuberculosis."
Mila Kunis dropped 20 pounds off her 5-foot-two-inch frame to play a ballerina in 2010's "Black Swan." "I could see why this industry is so f*cked up, because at 95 pounds, I would literally look at myself in the mirror and I was like, 'Oh my God!' <a href="http://www.eonline.com/news/marc_malkin/mila_kunis_black_swan_weight_loss/211623" target="_hplink">she told E! News</a>. "I had no shape, no boobs, no ass .. All you saw was bone." Kunis continued: "In real life, I looked disgusting, but in photographs and on film, it looked amazing."
Rooney Mara went through a total transformation for her role as Lisbeth Salander in "The Girl with the Dragon Tattoo." Not only did she chop and dye her hair and get several piercings, she "starved" herself to lose weight for the role. "[Director] David [Fincher] didn't want me to lose any weight; that was something that I wanted to do that he was, kind of, opposed to," <a href="http://www.hollywoodreporter.com/race/girl-with-dragon-tattoo-rooney-mara-david-fincher-275307" target="_hplink">she told The Hollywood Reporter.</a>
Natalie Portman had to look near skeletal to play a crazy ballerina in "Black Swan." Like Mila Kunis, she also dropped 20 pounds and scored the Academy Award for Best Actress in 2011. Portman trained in ballet for a full year before filming in order to portray the ballerina. "I mean, I had never gotten that much training -- to be doing five-to-eight hours a day of [it] was really a challenge," she <a href="http://www.usmagazine.com/celebrity-body/news/natalie-portman-opens-up-about-shocking-weight-loss-for-black-swan-20103011" target="_hplink">told <em>Us Weekly</em>.</a>
50 Cent lost a <a href="http://www.huffingtonpost.com/2010/05/26/50-cent-loses-a-lot-of-we_n_591102.html" target="_hplink">shocking amount of weight</a> for his role in "Things Fall Apart," in which he plays a cancer-ridden football player. The actor and rapper said he dropped from 214 pounds to 160 pounds over the course of just nine weeks with a liquid diet and working out three hours a day.
Christian Bale has put his body through hell for movie roles. The action lost nearly 65 pounds by eating only 275 calories a day over the course of four months, for his role in "The Machinist." The 121-pound actor then bulked up to 190 lbs in just five months to play Batman in "Batman Begins" and he later gained another 30 pounds of muscle for "The Dark Knight." "It was like a massive shock to my body because of what I was trying to get it to do," Bale told the BBC. "My metabolism had to get back up to speed, because my heart had gotten used to a whole different way of living."
Beyonce lost 20 pounds to play Deena Jones, the lead singer of the Dreamettes, in 2006's "Dreamgirls." "At the beginning (of filming), I was my normal weight,"<a href="http://www.people.com/people/article/0,,1196362,00.html" target="_hplink">she told <em>People</em></a>. "I actually gained a little bit, but then I lost 20 lbs. when I went from young Deena to old Deena. I wanted it to be something more than just make-up and hair. I wanted to see the change."
Tom Hanks has challenged his body to fit the role throughout the years. He gained 30 pounds in 1992 to play an alcoholic baseball coach in "A League of Their Own," and lost all of it and more for the 1993 movie "Philadelphia," where he played an AIDS patient. Years later he lost more than 50 pounds to portray a plane crash survivor in "Cast Away."
Seth Rogen shed 30 pounds in 2009 for his title role in 2011's "The Green Hornet" by eating right and working out. "No...I did not do any experimental injections! It's just diet and exercise. It works!" <a href="http://www.longislandpress.com/2011/01/17/seth-rogan-interview-the-green-hornet/" target="_hplink">he told the Long Island Press in 2011.</a>
Former "Lost" star Matthew Fox made himself almost unrecognizable for his role as a cage-fighter in 2012's "Alex Cross." "The amount of dedication and the weight loss is this much of where he went," <a href="http://moviesblog.mtv.com/2012/06/27/matthew-fox-alex-cross-tyler-perry/" target="_hplink">his co-star Tyler Perry told MTV</a>. "He really went to where ever he had to go. I don't even want to know what dark places he went to to get that character, but he was amazing."
Matt Damon lost a startling 50 pounds for 1996's "Courage Under Fire," but it came at a price. <a href="http://abcnews.go.com/Entertainment/Oscars/matt-damon-stars/story?id=9957289#.UEjiuaTLxwY" target="_hplink">According to ABC News</a>, he lost 40 pounds in under three months for the role, and it left him with adrenal gland damage.
After having a baby, Jennifer Hudson had to drop her pregnancy weight quickly to portray Winnie Mandela in 2011's "Winnie." "Whatever it takes to morph into a character I'll do it,"<a href="http://www.people.com/people/article/0,,20386960,00.html" target="_hplink"> Hudson told <em>People</em></a>, adding that she dropped the pounds by working out and exercising portion control through Weight Watchers.
Colin Farrell had to lose weight for his role as a war reporter in Bosnia in 2009's "Triage." "I lost weight because my role demanded it," <a href="http://www.people.com/people/article/0,,20200771,00.html" target="_hplink">Farrell said at a 2008 press conference.</a> "It was all very healthy."
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