Anne Hathaway "barely ate anything" and turned to cigarettes ahead of awards season a decade ago.
The 36-year-old actress admitted she felt pressure to have "a certain body" because although her career was flourishing, she was gripped with "feelings of inadequacy, insecurity, nervousness and anxiety" and didn't look after herself properly.
Speaking on 'The Jess Cagle Interview' on PeopleTV, she said: "I did everything so wrong for so long.
"I'm not big on looking back but I remember 10 years ago being so scared going into the whole awards season and doing what I thought I was supposed to do, so I barely ate anything at Christmas...I thought movie stars had to have a certain body. I was just smoking, just smoking my nerves away and wasn't nourishing myself."
But the 'Serenity' actress - who has son Jonathan, two, with husband Adam Shulman - admits she's changed her outlook drastically since then.
She said: "I just figured out how to say thank you to life by taking care of myself. By not apologising for taking up space, which is not something I knew how to do 10 years ago.
"It's been a journey. I don't look that different, but I just feel like the inside has transformed so much."
And Anne isn't particularly interested in what her critics have to say about her - but if they are going to be negative, she'd rather they were "witty" in their cutting remarks.
She said: "Everybody's entitled to their opinion. What I appreciate is when the negativity has some intelligence behind it. What I don't like is lazy negativity. If you're going to take someone down, have a point of view! Be witty, maybe pun a little!"
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