Unbelievable Movie Transformations and the Actors Who Pulled Them off ...

1. Christian Bale

Starting off this list of actors who transformed their bodies for a role is Christian Bale. As attractive and fit as Bale was for the Batman series, his '70s character in 'American Hustle' was anything but. Sticking to a diet of cheeseburgers and donuts, Bale gained a whopping 43 lbs for the role. Must be interesting to be required to eat junk for work! He also shaved his head to achieve the balding look for his character.

2. Matthew McConaughey

You're probably familiar with the incredible transformation this Hollywood Hunk went through to become his character, a man diagnosed with HIV. The actor lost 50 lbs for the role and truly captured the image he was looking for. The intense weight loss proved to work in his favor, not only because 'Dallas Buyers Club' was such a huge success, but because he won an Oscar, and rightfully so.

3. Tom Hanks

Hanks' grungy, ship-wrecked appearance for 'Castaway' was au naturel. Production was postponed for a whole year so that the actor could lose 50 lbs and grow out his hair and facial hair. No hair pieces for Hanks--his look was the real deal.

4. Charlize Theron

Charlize is undoubtedly a natural beauty, but for her role in 'Monster' as a former serial killer and prostitute, she needed to mask her look by gaining weight, wearing unflattering makeup, and prosthetic teeth--Theron was practically unrecognizable in the film. Regardless, she won an Oscar for her compelling performance.

5. Natalie Portman

For her role as an obsessive ballerina in 'Black Swan,' Portman lost 20 lbs on a diet of carrots and almonds. She also worked out for an uncanny amount of time each day. Portman's strict routine was parallel with her character's personality, which caused her to reveal to Entertainment Weekly that she "understood how you can get so wrapped up in a role."

6. Rooney Mara

Mara's character in 'The Girl with the Dragon Tattoo' was anything but glamorous, and accordingly, the actress received several facial piercings, and had her hair chopped off and her eyebrows bleached.

7. 50 Cent

Remember when photos were released of the always muscular and chiseled rapper looking as though he were extremely ill? Makes sense because he was preparing for a role as a football player with cancer in 'All Things Fall Apart,' for which he shed an unbelievable 54 lbs. Fiddy went on a liquid diet and strict gym routine, but unfortunately the movie was a huge flop.

It's really impressive and also a bit scary to consider the things that actors will put their bodies through to portray a certain character. While many of these transformations were downright unhealthy, they really helped to convey the spirit of the film and helped the actors to truly embody their characters. What do you think about some of these transformations?