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Gwen Stefani

Gwen Stefani's as blonde as it gets, and her platinum hair color is a definite throwback to some of Hollywood's biggest sex symbols, like Marilyn Monroe, Jayne Mansfield, and Jean Harlow.

If Stefani was looking for a subtle color change, Pelusi recommends "lowlights in a deeper blonde color woven throughout the hair." He says it would require touchups every three or four weeks, and over time Stefani could gradually move into a deeper color, kinda like the color peeking out in the back in this photo. But we don't think she's ditching her bleach anytime soon ...