Lily Collins feared her eating disorder would leave her infertile.
Lily Collins
The 27-year-old actress used to binge on "every type of junk food possible" and then force herself to vomit, and her problem took its toll on her health and appearance.
She wrote in her autobiography 'Unfiltered: No Shame, No Regrets, Just Me: "My hair and nails became brittle. My throat burnt and my oesophagus ached. My period stopped for a couple of years. I was terrified I had ruined my chances of having kids.
"I was convinced that I had f***ed myself up beyond repair."
In the upcoming tome, the 'To The Bone' star explained how she felt her eating disorder began when her famous father Phil Collins divorced his third wife Orianne Cevey and a "terrible disconnect" grew between them as she got older.
In an extract, published in The Times Magazine, she said: "Many of my deepest insecurities stem from these issues with my dad."
The 'Mirror, Mirror' actress wrote a loving letter to her father but she insists he hasn't seen it yet.
She said: "It's not something I really want to email. I want to present it physically. I want to be in the room, you know? That's the kind of thing that you don't just send off willy-nilly."
Lily previously admitted writing her book and playing a young woman gripped by an eating disorder in her new movie 'To The Bone' helped her face her "fear" of eating disorders "dead on".
She said: "This was definitely a more dramatic role for me. I suffered with eating disorders when I was a teenager as well.
"I wrote a book last year, and I wrote my chapter on my experiences a week before I got [writer-director Marti Noxon's] script. It was like the universe putting these things in my sphere to help me face, kind of dead on, a fear that I used to have.
"It did require a different set of emotional skills, to go back in time for me, with my experiences. So definitely a different type of film for me to do, very, very personal."
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