The X Factor judge has sparked concern in recent months after displaying a slimmer figure at auditions, something she partly attibuted to the death of her father-in-law.
And now she has reiterated in the new ES Magazine that fans shouldn't worry about her.
"I am very happy and very healthy," she said. "Every woman has a different body type and handles stress and grief differently. I was a ballerina from a child, so I have really good muscle memory. When I work out, I can look like a tennis player. If I don't, I look different."
Cheryl, 32, also said she was fed up with bodyshaming comments and was concerned at the pressure now facing the younger generation of female celebrities.
"I can take whatever they throw at me after 13 years, what worries me is what it's doing to the younger generation," she said. "And some of the people writing this stuff are women. There is no sisterhood. The body shaming has to stop. It's bulls***. Something has to be done, changed, even if it's done in law."
Cheryl initially hit back at comments about her size via Instagram, saying: "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."
She later told The Mirror: "It's nice that people are concerned, but, honestly there's no cause for concern. You can see I am completely and utterly well and happy."