Meghan Trainor's positive-body image hit "All About That Bass" toppled Taylor Swift's "Shake It Off" from the top spot on Billboard's Top 100. Swift's song sat atop the list for the past two weeks. Swift might not notice, being embroiled in a media-generated feud with Katy Perry. The 20-year-old chart-topper is becoming a pop culture phenomenon because of her empowering message for curvy girls.

In an interview Trainor gave Billboard in July, the singer said "You know how the bass guitar in a song is like its 'thickness,' the 'bottom'? I kind of related a body to that. My producer [Kevin Kadish] had the title and said that none of his prior co-writers could figure out what to relate that to. So, I said, 'What about a booty? Let's talk about that!' From there, it turned into, let's do a song about loving your body ... and your booty."

Meghan Trainor's blockbuster single "All About That Bass" declares that the singer is happy, powerful, desirable and "perfect" because who she is and not I spite of it. The song has a catchy retro R&B beat and it's been flying up the charts as a summer hit.

Trainor is from Nantucket, Mass. Trainor says she can write a song in 45 minutes. She began her career as a songwriter by writing songs for country music stars Rascal Flatts. Trainor wrote two songs on Rascal Flatts' new album "Rewind."

 "I wrote the song and started pitching it for like four months and no one wanted it," Trainor told Out magazine about her new single. Now she has a record deal with LA Reid. Trainor released her debut EP, "Title," which includes her follow-up single "Dear Future Husband."