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Josh Brolin Gained 73 Lbs. for Legacy of a Whitetail Deer Hunter
Josh Brolin, 48, shared a before-and-after photo of his weight gain on Instagram on Monday, showing himself at 167 lbs. and 240 lbs. The actor previously said on The Tonight Show with Jimmy Fallon that he had gaind 40 lbs. for his role in Legacy of a Whitetail Deer Hunter, but it's unclear if the additional 33 lbs. were also for the role.
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Andrew Garfield Lost 40 Lbs. for Silence
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Adam Driver Lost Weight for Silence
"That visual part of storytelling, I don't think I've taken it to the extreme before," the actor, 33, told Interview magazine. "It's an interesting thing."
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Robert Pattinson Slimmed Down to a 28-Inch Waist for The Lost City of Z
Robert Pattinson dropped some serious pounds to play an Amazon explorer in The Lost City of Z.
"I had literally eaten nothing for the entire time," Pattinson, 30, told PEOPLE. "I loved it afterwards for like a week in London where I had a 28-inch waist. I was like, 'Ooh! Skinny jeans!' That lasted for, like, three days."
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Renée Zellweger Gained 'a Few Pounds' for Bridget Jones's Baby
"I put on a few pounds," the actress, 47, told Vogue UK. "I also put on some breasts and a baby bump. Bridget is a perfectly normal weight and I've never understood why it matters so much."
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Jeffrey Dean Morgan Lost 40 Lbs. for Texas Rising
Jeffrey Dean Morgan went to extremes to lose weight to play "Deaf" Smith on the History Channel miniseries Texas Rising.
"I got there and I was probably 175, I left I was about 135," Morgan, 50, said on Today. "I ate a can of tuna fish a day. I did it in the most unhealthy way I could. I didn't consult a doctor or anything. [...] By the end of the movie I just looked like hell."
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Jared Leto Gained 'A Lot of Weight' for Suicide Squad
"I'm trying to gain a lot of weight," he told Billboard in February 2015. "It means I have to eat every couple of hours, and I'm terrible at eating a lot."
Leto, 45, previously lost 30 lbs. for his Oscar-winning role in Dallas Buyers Club, gained 60 lbs. to play John Lennon's assasin Mark David Chapman in the 2007 film Chapter 27, and lost weight to play a junkie in 2000 for Requiem for a Dream.
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Jennifer Aniston Stopped Going to the Gym to Gain Weight for Cake
"At first I was thrilled because I said, 'This will be so great! I don't have to work out,' " she told reporters. "After a few weeks it really does start to affect your sleep, your stamina throughout the day, your mood."
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Tom Hanks Says He Can No Longer Gain Weight for Roles Because of His Diabetes
Tom Hanks slimmed down for Philadelphia, Castaway and Forrest Gump, and has gained weight for other roles. But in October 2013, the Oscar-winning actor said he can no longer allow his weight to fluctuate drastically because of his Type 2 diabetes diagnosis.
"I think that's more or less a young man's game," Tom Hanks told the BBC of gaining weight for roles. "I don't think I'm going to take on a job and see to it that I can gain 30 lbs."
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Matthew McConaughey Lost 50 Lbs. for Dallas Buyers Club
Matthew McConaughey lost a drastic amount of weight to play an HIV-positive man in 2013's The Dallas Buyers Club. The actor, 47, weighed 185 lbs. when he began losing weight, and thought he would stop at 145 lbs.
"I was going around and people were going, 'Hey, are you feeling all right?' " McConaughey told PEOPLE about the reactions to losing the first 40 lbs. "But then I hit 135 lbs. I ran into somebody and they didn't just ask if I was all right, they said, 'My God, we need to get you some help.' And I thought, 'There we go. That's the perfect spot.' "
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Matthew McConaughey Gained 47 Lbs. for Gold
McConaughey proved his dedication to his roles once again by putting on 47 lbs. to play Kenny Wells in the upcoming movie Gold.
"I enjoyed getting into Kenny and doing my research and all of a sudden I looked in the mirror and was like, 'You put on a lot of weight, McConaughey,' " the actor said, according to Variety.
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Anne Hathaway Lost 25 Lbs. for Les Misérables
Before shooting Les Mis, Anne Hathaway, 34, lost 10 lbs. by going on a strict cleanse. She lost another 15 lbs. in two weeks by living off of two thin squares of dried oatmeal paste per day.
"I had to be obsessive about it," she told Vogue. "The idea was to look near death. Looking back on the whole experience — and I don't judge it in any way — it was definitely a little nuts. It was definitely a break with reality, but I think that's who Fantine is anyway."
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Christian Bale Lost 63 Lbs. to Play The Machinist
Christian Bale lost 63 lbs. to play a man whose health deteriorates after not sleeping for a year in the 2004 film The Machinist. To lose the weight, Bale, 42, stuck to a diet of coffee, cigarettes and an apple a day.
"I wouldn't have done that amount of weight loss if I hadn't thought the movie itself was worth seeing," he said.