She said she saw herself like an alien while she had the skin condition and felt "more disconnected from myself than I think I ever had".
Speaking at the Women in the World conference, Delevingne said she reached a turning point. "I wanted someone to go 'you need to take a break, you need to look after yourself'. No one did.
"I eventually said no and I eventually took a break. I took the advice of Kate Moss who picked me up off the floor passed out.
"I started writing - writing is something that really saved my life. I would read what I had written and it would be like someone else was speaking to me. It was a very strange experience.
"Then after that I found yoga, which was a huge thing for me."
Delevingne also shared a poem that she had written.
Ending with advice for the audience of young women, she said: "My message has always been to love yourself, to embrace your flaws.
"The cracks within us are the beautiful parts that need to have light shone on them."
-AAP
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