7. Jennifer Lopez (42)

While many a pop star has tried their hand at acting, it’s a lot less common for an established screen siren to make the leap into music and succeed. But that’s exactly what Jennifer Lopez did in 1999. The recent Vogue cover girl helped fuel the Latin explosion of the early '00s — along with Ricky Martin and Shakira — and seamlessly juggled film, music and fashion careers before breaking her streak of Top 10 albums with 2007’s Brave. Happily, her stint as a judge on American Idol reminded everyone what they were missing, and Pitbull’s go-to-girl is now ready to dance again.