Speaking to Now magazine, the 31-year-old former Girls Aloud star said Miley's "wild child" behaviour reminded her of herself in her younger years.
"I do see a little bit of the old me in her, but I think she's more out there than I ever was... I can see why Miley twerking with that foam finger caused a bit of a stir. I mean, it was a bit much.
"I was called the wild child of Girls Aloud, but that was me just playing up to the role. It wasn't really me. But she's all about the shock factor. She's getting headlines, so it's probably great for her sales and her image."
And she suggested that Miley could be reacting against her previous reputation as a squeaky clean child star.
"In her defence, she's having a bit of fun, isn't she? I think it's just a big reaction to the way she used to be.
"Miley got into it young and is totally rebelling, like Britney Spears did. Americans seem to go to extremes very quickly."