Evanna Lynch used to troll herself

She told the Sunday Times magazine: “An eating disorder is your worst bully. The meanest person lives in your own head, so everyone beyond that you can deal with. It wasn’t a shock to me if I was criticised. I was braced for it, I expected it.

“I was addicted to negative thinking, always seeing the worst thing about myself because that felt safe.

“I thought, if I’m the meanest person to me, then nobody can hurt me. So when I got this level of fame and when I found people on the internet saying horrible things about me, it was a sense of community.

"They echoed my horrible thoughts and I wanted to submerge myself in it. You think, if I go to the very darkest place it will all be OK.”

But although Evanna felt "safe" amongst her haters, her search for negative remarks became her focus and she eventually realised her life would be "cold and empty" as a result.

She said: “I kept hearing those words echoed in my daily life when I looked in the mirror.

"I thought, if I keep doing this I’ll never achieve anything, I’ll just crawl in a hole and give up. I’ll be ‘safe’ with all these nasty, bitter people, but my life will be cold and empty.”

The actress now considers herself fully recovered from her eating disorder and believes her positive outlook has been vital.

She said: “I learnt how to change my mindset. I’m really disciplined about thinking positively,”