I Tried the K18 Hair Treatment Simone Biles Swears By & My Blowout Is Still Going Strong 7 Days Later

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I love an assignment that sends me to the hair salon , whether I’m trying a trendy new haircut or helping nail down the best blow dry brush on the market. It’s a tough job—cue the sarcasm—but someone has to do it. During my most recent outing to Spoke & Weal in NYC, I was on a mission to test out Simone Bile’s go-to hair treatment, the K18REPAIR™ . While noshing on a cookie shaped like Biles herself (so meta), the stylist and I got down to business.

Catrina Yohay

As a hot tool lover and recent hair dye convert, I was beyond excited to test out the hair repair service that helped Biles maintain a healthy mane during the Olympics when all eyes— including the haters —were on her. I went in cautiously optimistic, not expecting a Cinderella transformation but hopeful that this wasn’t just another celeb-endorsed flop (Biles is an official ambassador for K18). The end result? Added shine, noticeable strength and a week-long blowout I’ll never forget.

Since 2020, K18 has been shaking up the haircare industry. Combining technology with the science of beauty, this fast-growing company has had viral hit after viral hit ( thanks TikTok ). But the signature K18REPAIR™ service that Biles loves so much can’t be bought at your local Sephora. According to the brand, it’s a professional-grade, in-salon treatment that helps preserve hair health and reverse damage. Leveraging the power of patented biotechnology, K18REPAIR™ helps strengthen and fortify the hair “to make it resistant to damage while providing lasting, biocompatible repair from bleach, color, chemical services and heat.”

Available at most salons ( check here to see if your local one offers it ), K18REPAIR™ also includes the viral hair mask Biles swears by for easy maintenance at home. “The K18 Molecular Repair Hair Oil and K18 Leave-In Molecular Repair Hair Mask have been game changers for me,” Biles says, “so my hair stays healthy amid all the stress I put it through, including with extensions. My hairstylist and I have really felt a difference in my hair after using K18 and she’s great about always having their products available to me, especially when I’m traveling or on shoots.”

Catrina Yohay

As for me, I’m here for the hype. On top of smoother strands and added shine, I could not believe my eyes when I woke up a full week after receiving the treatment to a blow-out that looked as good as new. Sure, the curls had fallen (heat, humidity and a busy week will do that) but the overall volume endured and there wasn’t a trace of oil or stringiness in sight.

Not only was I able to skip a few wash days, but I also didn’t feel the need to break out any hot tools for touch-ups (meaning while repairing and reversing, the treatment also helped me prevent further damage). That deserves high marks in my book.

Rihanna, Sophie Turner and Selena Gomez Love The K18 Leave-In Hair Mask, So I Tested It on My Curls

More Hair Heroes from K18

K18 Leave-In Molecular Repair Hair Mask

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K18 Molecular Repair Hair Oil

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K18 AirWash™ Dry Shampoo

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