Adrien Brody lost fourteen kilograms to play Wladyslaw Szpilman in The Pianist. It was worth it though, he won an Oscar for his performance.
Beyonce played singer Deena Jones in the film Dreamgirls. She lost six kilos to be able to play the singer.
Tom Hanks lost fifteen kilos to play Andrew Beckett in the film Philadelphia. His reward for all that dieting? An Oscar and a Golden Globe!
Lost Star Alex Fox lost an unbelievable twenty-two kilograms to play serial killer Picasso in the film Alex Cross.
Jared Leto starred alongside Matthew McConaughey in Dallas Buyers Club. Both actors lost a lot of weight, Leto lost a whopping eighteen kilograms! They both won Oscars for their performances.
Jennifer Hudson and Christian Bale win joint first place when it comes to which actors lost the most weight for a role. Jennifer lost an astounding 28 kilos for her performance in the film Winnie Mandela
Liam Neeson lost ten kilos for his role in Silence.
Chris Hemsworth went on an extreme diet for his role in In the Heart of the Sea. He had to lose 15 kilos in a very short space of time.
usually graces our screens as muscly eye candy, but he lost 19 kilos to play Ron Woodroof in Dallas Buyers Club. He won a Golden Globe and an Oscar for his performance.
Natalie Portman played the lead in Black Swan. Just like fellow actress Mila Kunis, Portman lost 10 kilos to star in the film, however while all that dieting did not pay off for Kunis, it did for Portman, who won an Oscar for her performance.
Christian Bale lost 20 kilos to star in The Fighter. He won a Golden Globe and an Oscar for his performance.
Mila Kunis lost 10 kilos to play a ballet dancer in the film Black Swan. She was nominated for an Oscar for her performance.
Tom Hanks lost 22 kilos to star in Cast Away!
Anne Hathaway won an Oscar for her performance as Fantine in the film Les Miserables. However, it was hard work, she didn't just have to give one of the best acting performances of her life, but she also had to lose eleven kilos to play the role.
Lots of celebs have gone on crazy diets just to make their performances all the more believable. Often, A-listers have to lose a lot of weight in just a few months.
Christian Bale underwent one of Hollywood’s biggest transformations. He lost a jaw-dropping 28 kilos to star in The Machinist!