Meghan Trainor is only 20 but she's already a candidate for Song of Summer 2014 with "All About That Bass," her infectious ode to curvy girls. "Yeah it’s pretty clear, I ain’t no size 2/But I can shake it, shake it, like I’m supposed to do," Trainor sings. "Cause I got that boom boom that all the boys chase/All the right junk in all the right places!"

She hardly has to worry about her size, but the Nashville native says she wrote the song as much for herself as for other girls with body-image issues. " I wrote it to help me as well," she told Cosmo. "And it has helped me because people have been complimenting me like, "Man, you look good in that video!" and I'm like, "Yeah I do!" If I help other people that's just another dream come true."

She penned penned tracks for Rascal Flatts and other big artists while still in high school

We can't get enough of the song—or the video created by  Fatima Robinson and Vine star Sione Maraschino. Check it out below.

You can also download "All About That Bass" for free on Trainor's website.

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