The X Factor judge sparked concern when she arrived at the first filmed auditions of the year in a crop top that highlighted her small frame.
Among those taking aim at her was controversial Katie Hopkins, who said: "Cheryl, love, you need a good roast dinner."
According to The Sun, singer Cheryl is frustrated by the interest in her size and insists she's eating lots and not trying to be skinny.
A source said: "She's mortified that people might think she's deliberately trying to look skinny. She has had a a stressful time but she's feeling really happy to be working again."
'Call My Name' star Cheryl herself hit out at body shaming comments earlier this month, saying she'd been under a lot of stress lately, particularly after the death of her father in law.
She said: "I am so sick and tired of it being ok to call somebody too thin or a 'bag of bones'. I would never dream of calling somebody too fat and that they should maybe cut down on their food intake? What is the difference? You have no idea what I have been through. Just losing my father in law v recently and everything that comes with that. Not that I am or should justify myself to anyone. (sic)"
"I'm so f***ing sick of people thinking it's ok to be mean or body shame anyone, " she continued. "And it's woman on woman. Have some respect and maybe think there may be reasons why before opening your mouth please. I am just tired of the ignorance...At some point it's just enough. Some people are naturally thin. My mother is all of 4'11 and six stone something. And is incredible healthy and happy.(sic)"
Cheryl, 32, continued filming auditions for the new series of X Factor in London yesterday, arriving at Wembley in a 1960s-style Valentino leather frock.
Check out Cheryl's hair transformation below:
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