Stars Who’ve Lost Weight, Packed On The Pounds For Movie Roles (PHOTOS)

This is dedication to the cause.

Genetically-gifted Hollywood stars like Matt Damon, Mila Kunis, Christian Bale and George Clooney have all had to forfeit their extreme good looks for the glory of the silver screen.

Cases in point: 28-year-old Kunis who reportedly shrank down to 95 pounds for her role in Black Swan. Or the stunning Charlize Theron, 36, who gained 30 pounds and won and Oscar for her role in Monster.

Who else has dropped — or gained — weight? Click through these 10 photos.

The A-listers spend lots of gym time perfecting their picture perfect looks, plus it can be very difficult for them to change their eating habits.

In some cases, it has really affected their health.

When Clooney gained 30 pounds in 2005 for his Oscar-winning role in Syriana, the extra weight gain caused a tear in his spinal tissue leading to a spinal leak.

He was in a lot of pain and unable to exercise through out production of the film, it was reported at the time.

Which body-changing photo of the stars shocked you the most? Sound off in the comments!