Lily Collins faces her eating disorder in new book and film

After years of struggling with an eating disorder, Lily Collins has done something she never thought she'd do.

"I never dreamed I’d be posing in a bikini on the cover of Shape. It’s a complete 180 for me. It’s a magazine about what it means to be healthy," the 28-year-old actress said in an interview in the July issue of Shape.

Not only does she appear on the cover in a two-piece but she is also shown posing in several different swimsuits for a photo spread in the magazine.

Collins' swimsuit display comes after more than half a decade of her suffering from an eating disorder that she kept hidden from friends and family.

Now fully recovered, Collins has a new definition of healthy.

"I used to see healthy as this image of what I thought perfect looked like -- the perfect muscle definition, etc. But healthy now is how strong I feel," she said. "It’s a beautiful change, because if you’re strong and confident, it doesn’t matter what muscles are showing. Today I love my shape. My body is the shape it is because it holds my heart."

Collins is opening up about her battle in a new book, "Unfiltered: No Shame, No Regrets, Just Me."

"I did consider that talking about my struggles with an eating disorder would overshadow my accomplishments as an actor, but I also knew this was something I needed to do to move forward as a human and an actress. I needed to let go," she told Shape. "Having suffered from an eating disorder doesn’t define me; I’m not ashamed of my past."

Collins also confronts her past in her new film "To the Bone," in which she plays a woman sent to rehab for an eating disorder.

"It was a new form of recovery for me. I got to experience it as my character, Ellen, but also as Lily. I was terrified that doing the movie would take me backward, but I had to remind myself that they hired me to tell a story, not to be a certain weight," she said. "In the end, it was a gift to be able to step back into shoes I had once worn, but from a more mature place."

"To the Bone," debuts on Netflix July 14.