Vanessa (Minnillo) Lachey knows a thing or two about running damage control on her hair.

Before she was the host of ABC's Wipeout or took on her husband Nick Lachey's surname, the star hosted MTV's now defunct Total Request Live with a head full of bleach-blonde highlights.

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"Letting my hair get over processed in general…my hair was literally damaged and falling out," she told Us Weekly about the effects of her hair look from yesteryear.

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The star has since traded the light streaks for deeper, caramel-colored ones, but regular blowouts and hours of heat styling have taken away her brunette locks' natural luster.

To salvage her hair, the star's pro introduced her to salon hair care brand Nioxin and their latest product, Diamax, a leave-in treatment that aims to deliver thicker-looking hair.

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"I started using [Diamax] daily in September and instantly noticed a difference. It creates a healthy scalp which promotes healthy hair," Minnillo told Us in NYC December 8. "Literally you just part your hair, spray it at the roots and part it again. You probably use 10-15 sprays on your hair, max, then you can flip your hair and blow it out or style it however."

"I use it on all my clients, because it's not just for those with thin hair -- it protects the hair as well," her hairstylist, Betsy Reyes, weighed in. "It's soft so you don't have that sticky of flaky element to it. You can use it on wet or dry hair. It's a unisex product."

Head to to learn more about Lachey and Reyes' favorite hair product.

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