Charlize Theron Gained 50 Pounds For a Role and "Dealt With Depression For the First Time"

If you've ever thought that being an actress is an "easy" gig, Charlize Theron is about to make you rethink that assumption. The Hollywood star recently stopped by The Ellen DeGeneres Show to chat about her new movie, Tully, and got real about how gaining weight for her role ended up having a negative impact on her mood and mental health.

In the film, Charlize plays the character of Marlo, a flustered mother who starts using a night nanny after welcoming her third child. Rather than taking a shortcut and using a "fat suit" to mimic the body type of someone who'd just given birth, the 46-year-old actress did things the old-fashioned way and packed on the pounds herself in real life — 50 pounds, to be exact. Talk about dedication!

So how did Charlize manage to gain that much weight? Potato chips were her secret weapon of choice. They were "everywhere," she told Ellen of the salty, crunchy snack. "I had a bag in my car, a bag in the bathroom, a bag in the kitchen, a bag on the couch, a bag in my trailer." Sure, eating Lay's nonstop may sound pretty darn magical at first, but there were harmful mental side effects that even Charlize didn't anticipate.

"The hardest thing for me was I wasn't prepared for how that amount of processed food would affect [my] mood. I dealt with depression for the first time," she admitted. The Tully actress added, "What they say about what you eat is kind of who you are is so true because I ate like a person who just didn't move, and I felt like that." Charlize noted how her unhealthy diet caused her to be "lethargic" and "tired all the time," and that it was hard to snap out of it because "it's more mental than it is almost physical."

See what else Charlize had to say about motherhood and weight gain in the interview with Ellen above, and then watch the trailer for her forthcoming film below.