Charlize Theron opened up about gaining almost 50 lbs for her role in “Tully” as she appeared on “The Ellen DeGeneres Show” Wednesday.

The 42-year-old, who plays an overwhelmed mother-of-two called Marlo in her latest flick, said losing the weight afterwards was “brutal.” However, she insisted she wanted to gain the weight herself so she could get into character to play the role the best she could.

Theron told the talkshow host, “In retrospect the film deals with what parenthood looks like today and it’s so insane to me that we live in a time where we share so much information, but for some reason when it comes to parenting there’s still so much stigma around it. We just don’t talk about a lot of stuff that parents go through.

“Mothers do this every single day. They get pregnant and they gain all that weight, it takes them a year and a half to lose it and if they don’t they get judged. I feel like I had to do it for the film. For myself as an actor I wanted to feel as much as I possibly could.”

Credit: Michael Rozman/Warner Bros.
Credit: Michael Rozman/Warner Bros.

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When DeGeneres, 60, then quizzed her on what she ate to gain the weight, Theron replied: “I ate a lot of everything, but my drug of choice is potato chips.

“I had a bag in my car, a bag in the bathroom, a bag in the kitchen, a bag on the couch… everywhere I went there was just a bag.”

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The actress said that her bad diet meant she was “tired all the time,” with her admitting: “I wasn’t prepared for how that processed food would affect your mood and I dealt with depression for the first time.

“I ate like a person who just didn’t move and I felt like that. That was a hard thing to break because it’s more mental than it is physical.”

Theron’s appearance also saw her open up about how her two children Jackson (Jacks) and August (Auggie) don’t get along as well as they used to.

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Style Evolution: Charlize Theron