Scarlett Johansson was named Esquire's sexiest woman alive for the second time this year and judging by her red carpet looks throughout the years, the title is well-deserved.

"I'm the only woman to win twice right?" she told the magazine. "You know, I gotta hustle. I'm a 28-year-old woman in the movie business, right? Pretty soon the roles you're offered all become mothers. Then they just sort of stop. I have to hedge against that with work-theater, producing; this thing with Esquire."

Scarlett Johansson's Hot Red Carpet Photos

Perhaps one of the reasons her look is often spoken about is because she looks great no matter what hair tone or style she tries. Her favorite hair color, however, is blonde.

"I'm naturally blonde so I feel most like myself when I'm blonde," she told Style.com in 2011. "I've had a lot of different hair colors for films I've done, but I always go back to blonde. I do love transforming my hair color or makeup look for a role and trying something new, though."

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The Avengers actress also revealed that she loves to wear her hair up, which she's done for several red carpet events.

"I really like to wear updos just because I think my face looks more elegant when I wear my hair up, but it depends on the event," she said. "If you're going to something young and fun and you want to feel sexy, it's nice to have your hair down and with a little bit of wave."

Scroll through our gallery to see some of her different hairstyles through the years.