Anne-Marie "stopped eating properly" as a teenager and then started buying pills on the internet to gain weight as she got older.
The 30-year-old singer used to restrict her died and only eat cheese sandwiches and crisps and her weight began to plummet after she took her GCSEs when she was 16, and she admitted she was "unhealthily" thin.
Writing in her new book 'You Deserve Better' - which offers support and advice to those struggling with their own issues - she admitted: “I stopped eating properly. I got really skinny — unhealthily so.”
And when she was 22 and on tour with Rudimental, the 'Ciao Adios' singer went to another extreme and bought pills online in a bid to gain weight to be more curvy.
She continued: “I’d been obsessed with being thin but I started to notice the girls they found attractive were curvy.
“Of course, me being me, I took that on board 110 per cent and totally changed my approach overnight. I started buying pills off the internet that made me put on weight. It was ridiculous, and dangerous.
“But I still wasn’t happy because I was still trying to be something that I wasn’t.”
Anne-Marie also told how she was close to a "full-on breakdown" following the release of her debut album, 'Speak You Mind', in 2018, resulting in her seeing a therapist and cutting down her work commitments.
She wrote: “I was so sad I couldn’t cry. I went to a CBT therapist for the first time. She told me I was on the verge of a full-on breakdown and that I was severely depressed.
“I stopped working for a bit, I pulled recording sessions and stayed at home.”
The 'Birthday' singer admitted having a therapist she now sees every week has been an essential source of support.
She added: “I don’t know if I’d be here without it.”
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