10 Hollywood Stars Who Gained Serious Weight For A Role

When Bulking Up Became Their Job

Who would not like to bulk up to look good. But for actors, bulking up means an entirely different story altogether. They have to go through heavy diet to reach the required weight gains for playing the specific character they had auditioned for. These are the top moments where actors had to gain a lot of pounds to become the character they were playing.

10. Russell Crowe - The Insider

In one of the great "de-glamorizing" roles of the '90s, Crowe, who was about to become a global icon in Gladiator, gained 35 pounds to play the middle-aged, out-of-shape tobacco-industry whistleblower. He also used a wig and aging makeup, making him nearly unrecognizable and earning him his first Best Actor nomination.

9. Matt Damon - The Informant

To play the schlubby, delusional, suburban-dad-turned-whistleblower, Damon happily gained 30 pounds. He said he had the time of his life, simply "eating everything I could see," including McDonald's, Doritos, and dark beer. The resulting "doughy" physique was the perfect, non-heroic look for the comedic and bizarre true story.

8. Mark Wahlberg - Father Stu

For this passion project, Wahlberg, known for his insane fitness, had to gain weight twice. He first gained weight to play the boxer, then gained even more to portray Stu's post-injury, bloated look. He gained 30 pounds in just six weeks, force-feeding himself 7,000 calories a day (and later 11,000), which he described as "absolutely horrible."

7. George Clooney - Syriana

To play the veteran, "doughy" CIA operative, Clooney (then known for his slick charm) gained over 35 pounds in a single month on a diet of pasta. He has said it was the most miserable experience of his career. The transformation was so jarring that it helped him disappear into the role, ultimately winning him the Academy Award for Best Supporting Actor.

6. Renée Zellweger - Bridget Jones Diary

For this career-defining role, Zellweger famously gained 30 pounds (and did it all over again for the sequel). In a time when Hollywood was obsessed with being rail-thin, her dedication to portraying a "normal" body weight—and her subsequent, much-publicized diet—became a massive cultural topic, and her performance was beloved.

5. Jared Leto - Chapter 27

To play John Lennon's assassin, Leto committed to a massive and dangerous weight gain. He gained a reported 67 pounds, primarily by drinking microwaved pints of ice cream mixed with soy sauce and olive oil. The transformation was so extreme and rapid that it gave him gout and forced him to use a wheelchair on set.

4. Charlize Theron - Monster

Theron's change was about more than just prosthetics. To physically embody the real-life serial killer Aileen Wuornos, she stopped exercising and "ate Krispy Kreme donuts" and potato chips, gaining 30 pounds. The combination of the weight gain, the prosthetic teeth, and her raw, de-glamorized performance was so total that audiences were stunned, and she won the Oscar for Best Actress.

3. Vincent D'Onofrio - Full Metal Jacket

This is still the unofficial record for a major film. To play the tragic, spiraling Private Pyle, D'Onofrio gained a staggering 70 pounds, bringing his weight to 280 pounds. He said the weight gain, which he did over seven months, was incredibly difficult, affecting his mood and even his joints, but it created one of the most memorable and haunting characters in war movie history.

2. Christian Bale - Vice

No one transforms like Bale. After losing weight for The Fighter, he had to gain it all back and then some to play the former Vice President. He gained over 40 pounds, shaved his head, and bleached his eyebrows. He famously said he "ate a lot of pies" to achieve the look, completely disappearing into the role and earning another Oscar nomination.

1. Robert De Niro - Raging Bull

This is the gold standard. De Niro first got into peak physical shape to play the boxer in his prime. Then, for the final part of the film, production shut down for four months. De Niro traveled to Italy, went on an "eating tour," and famously "ate his way through Northern Italy." He returned having gained 60 pounds to portray the older, washed-up LaMotta, a shocking transformation that won him the Oscar.