Tess Holliday has said she had "no idea" she could be struggling with anorexia before she was diagnosed with the condition, because she was not underweight.
The American model told ITV's Good Morning Britain she is now "healthier and happier" than ever before after dealing with the condition.
Holliday said she previously wanted a "badge of honour that I was this person in a larger body not eating".
She said the media usually portrays people with anorexia as being "extremely underweight".
"But that's part of why I had no idea that I could even struggle with anorexia," she said.
"So you know, that's part of why I wanted to share my story, because I know my body very well, I knew myself very well.
"So to hear that I could be, you know, living in a larger body and struggling with a disorder that's been presented differently really threw me for a loop, and I figured other people were dealing with the same thing."
'I was confused.'— Good Morning Britain (@GMB) May 13, 2021
Tess Holliday opens up about her battle with an eating disorder. Tess became 'the first size 22 model' to sign with a major agency in 2015. pic.twitter.com/lMFnZcn0rn
Holliday said she has been "struggling with eating disorders most of my entire life".
"I restricted, I wouldn't eat, I would go sometimes an entire day without eating anything," she said.
Holliday said it is "empowering" to be able to speak about her disorder, adding: "This is not a fun thing to be talking about.
"But the reality is, you know, if someone that can be as knowledgeable about their body and body positivity and loving yourself, if I can be struggling with an eating disorder like anorexia, I know that there's other people that are dealing with it."
She said the pandemic had been a "blessing" for her "because it allowed me to slow down for the first time in my career and really reflect on myself".
"And it was through that kind of downtime that I realised that something wasn't OK with me," she said.
"I didn't feel good. I just wasn't myself."
She said there are "so many folks that aren't getting the diagnosis due to weight bias stigmas".
Holliday said getting a diagnosis was "revolutionary".
"Because of getting the diagnosis, I finally understood that I am fat because I was starving myself, and that's really hard for people to understand," she said.
"And I know that's not the case for everybody, but for me, I was restricting so much that I was harming my body.
"So now I'm able to feed my body, take away the guilt from it and take care of myself and the weight itself in the way that I need, and I feel better.
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