Olaplex No.9 Bond Protector nourishing hair serum protects strands from damage

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Olaplex fans, rejoice. You are about to add another “number” to your hair routine. This time it’s about protecting the strands before the damage starts instead of fixing it. Olaplex No. 9 Bond Protector Nourishing Hair Serum promises to reduce tangles and static and increase shine, style retention (meaning your curls won’t fall flat) and bounce. It also claims to protect hair from environmental aggressors like pollution and heat up to 450 degrees. It’s pretty much your all-in-one leave-in.

“I see firsthand what pollution does to hair when I look at and touch my client’s hair,” says colorist Tracey Cunningham STYLECASTER. “It’s damaged, dull and lifeless.” She uses Olaplex #9 to make hair shiny with less frizz and even to reduce drying time. She recommends using the leave-in serum on damp or wet hair to get the most protection from free radicals. This comes from the addition of red algae extract, an antioxidant that helps block pollutants and neutralize harmful free radicals like tobacco smoke, polluted air, UV rays, etc. It also contains this patented ingredient to repair broken bonds for stronger hair.

Cunningham works the serum upwards from ends to roots and says you can air dry for soft texture or blow dry for a smooth finish. “If my clients have waves or curls, I like to use a diffuser,” she adds.


I followed Cunningham’s instructions and applied Olaplex No. 9 right out of the shower to wet hair. I usually apply a few products, one for hydration, one for detangling, another for heat protection. I like that it’s an all-in-one product. I love that the formula is smooth and lightweight and doesn’t weigh my fine hair down. This is likely thanks to the addition of sodium hyaluronate and panthenol, two moisturizing ingredients usually found in skincare.

I have this weird mix of fine hair that is also dry and frizzy from bleach damage so I need the right amount of moisture that won’t make my hair fall flat and that fits perfectly. After drying my hair with my Dyson Airwrap, I noticed my locks were smoother and shinier than usual. I also had a lot more volume and bounce. Everything from a single product? Pretty impressive.

Grab Olaplex #9 Now at Sephora.

STYLECASTER |  Interview with Ashley Benson

Melissa R. Brumfield