Lily Collins is set to star in Netflix’s “To The Bone,” a controversial movie which chronicles a young woman’s struggles with anorexia. For the role, the actress was forced to lose a significant amount of weight, which she says was an eye-opening experience for her.

Collins has been open about her own struggles with eating disorders, but signing on for “To The Bone” provided her with a new perspective on society’s obsession with being thin and the misunderstanding of body image issues. In an interview with The Edit, the 28-year-old recalled leaving her apartment one day after she’d been dieting for some time for the part. She ran into a friend of her mother’s, who praised her new, gaunt appearance.

“I was leaving my apartment one day and someone I’ve known for a long time, my mom’s age, said to me, ‘Oh, wow, look at you!’” she shared (via Us Weekly). “I tried to explain [I lost weight for a role] and she goes, ‘No! I want to know what you’re doing, you look great!’ I got into the car with my mom and said, ‘That is why the problem exists.’”

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There were moments in the film, according to Collins, that really resonated with her. She told The Edit her “heart dropped” when she saw just how thin she’d gotten for “To The Bone.” Co-star Carrie Preston, who plays Collins’ step-mother, snapped a picture during one particular scene, later showing it to the actress, who’s genuine reaction to the image was taped. She admits that when her mother saw the moment on film, it clearly hit her hard as well.  

“I saw myself in the photo and my heart dropped,” she said. “So when my mom saw the film, she saw Lily’s reaction because she knows me the best.”

Collins added, “The first time she was a bit in shock. The second time I looked over at the end and she was sobbing; it really hit her hard.”

The “To The Bone” star previously opened up about her personal struggles in detail in an interview with Shape. She told the magazine she suffered from anorexia and bulimia, though she kept both a secret from friends and family. It wasn’t until Collins was able to open up about her battle that she figured out who she really was, and was able to leave her disordered eating in the past.

“My perspective on other people’s view of me was based on this disorder being a secret. But the more open I became about it, the more I was able to be myself,” she says.

Collins went on to publish a book called “Unfiltered,” which detailed her experience with eating disorders. The book wound up being “even more honest than I was intending,” she told Shape. While she’s gotten past her eating disorder, Collins says she’s still discovering just how much she was hiding from the world.

“I didn’t realize I’d cover so much,” she said.

Netflix released the first official trailer for “To The Bone” on June 20. The trailer provides a quick glimpse at main character Ellen’s disorder as she forgoes full meals for coffee and does crunches to burn off calories quick. Her disease continues to spiral.

Ellen visits with Dr. William Beckham (Keanu Reeves), who notices her protruding bones. He warns her that he’ll stop treating her if she doesn’t take her recovery seriously. She doesn’t and things only get worse.

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Ellen faints at the hospital ahead of a checkup. Her mom decides enough is enough and checks her into a facility. There, she meets and connects with Luke (Alex Sharp), who’s on the road to recovery.

As Ellen attempts to get better, she’s urged to sit down with her family to discuss the repercussions of her disease. During their sit down, sister Kelly (Liana Liberato) opens up about the anger she’s been feeling. She claims she doesn’t have a sister, which cuts Ellen deep.

“To The Bone” premieres July 14 on Netflix.