Christina Aguilera over the years: 21 Sexiest looks (Photos)

Slideshow posted in Photos | Thursday, September 19, 2013

1 of 21: Christina Aguilera, a co-judge on the NBC singing competition series 'The Voice,' walks the red carpet at the network's summer 2013 press tour event in Beverly Hills, California on July 27, 2013. ( Photo / Tony DiMaio / Startraksphoto.com)