Demi Lovato's Hair Color Evolution

At just 19 years old -- she celebrates her big 2-0 on August 20 -- Demi Lovato has gone through enough hair changes to last her a few decades. In fact, in the past year alone, the singer and X Factor judge has sported almost every color under the sun.

Demi Lovato on January 11, 2012, May 24, 2012, and July 22, 2012.Credit: Jon Kopaloff/FilmMagic, Sean Mathis/FilmMagic, Kevin Winter/Getty Images

In this exclusive video, Us Weekly's Beauty Director, Gwen Flamberg, and Fashion Director, Sasha Charnin Morrison, recap some of Lovato's biggest statement-making looks. Among the color chameleon's biggest hair switch-ups? Rocking ombre at the 2011 MTV Video Music Awards and becoming a full-out redhead in November.

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Lovato then brightened up her look, debuting a honey blonde color at the X Factor announcement in May where she and Britney Spears were named to the show's judges panel. But she didn't stay a total towhead for long -- this summer, she's been experimenting with rainbow, candy-colored highlights.

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"I love changing my hair a lot -- I think it's fun," Lovato told Allure.com in an August 2012 interview. "I used to always want to dye my hair blue and purple and pink when I was younger. But I was busy trying! to make it in the industry as an actress, and it was hard to go in for auditions with blue hair. And so when I heard of the dip-dye trend, I loved it, and I felt like I could finally dye my hair blue. You know you've made it when you can dye your hair blue."

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Lovato tried out azure locks at the 2012 Teen Choice Awards in Universal City, Calif. on July 22.

Watch the video above and tell Us: What color do you think works best on Lovato?