The singer insisted that she's never been put under pressure to lose weight and is content with her image.
She told Celebs On Sunday: "No-one's ever told me to lose weight or anything like that. I don't rely on my t*ts to have hits.
"How I look has never been a big part of my life. I've never looked at a magazine and thought, 'That's how I need to look if I want to be successful in life'.
"If you compare the way I look to big artists like, say, Katy Perry, I'm living proof it's all about the music because there's nothing else I'm relying on to do well."
However, the 22-year-old admitted that she is trying to experiment more with her wardrobe.
She explained: "I'm trying to make more of an effort with my style.
"I'm a woman now. I like wearing three-quarter length dresses and things because I don't like having my thighs out, but I am trying new things."