"I had all these nasty comments saying I looked like Pete Burns and that my face had melted," she told Now magazine.
Insisting she hasn't had any surgery, she went on: "They were saying I'd had cheek implants, my chin done, my nose, fillers and Botox. If I'd had all that work, I wouldn't be able to bloody move my face!
"Back in the day, you didn't have this direct line to celebrities that you do now - you were more shielded.
"Everyone's entitled to a comment, but comments can become trolling when it's put in an aggressive way."
Natasha - who is preparing to go out on the road with the Kittens and the other 'Big Reunion' bands as part of their nationwide arena tour - previously admitted in the past to using Botox, but stopped because she didn't like it.
She told Closer magazine earlier this year: "I had a little bit of Botox five or six years ago, that's all. I didn't like it and haven't had it since."
Atomic Kitten recently revealed they were back in the studio recording new music following their appearance on 'The Big Reunion'.