Get up close and personal with exclusive, inspiring interviews and taste profiles delivered with a cheeky twist to your inbox daily.

Success! You’re all signed up. 🎉
Please enter a valid email address.

By subscribing to our email newsletter, you agree to and acknowledge that you have read our Privacy Policy and Terms.

K18 is Here to Save Your Processed Hair

Bad keratin treatment? Blow out addict? Here’s how to heal that damage.

We Tried It
Maraya Fisher's K18 Review
Photo: Courtesy of Maraya Fisher

I have put my hair through hell. As a medium-to-dark brunette who regularly subjects her hair to the trauma of bleaching it Anya Taylor-Joy platinum, I do my best to mitigate the damage. When I first started dying my hair over five years ago, Olaplex was the standard salon treatment—it was either automatic with the color service or a strongly recommended addition. But even with Olaplex, buckets of argan and jojoba oil serums, frequent haircuts, and heat styling abstinence, I always had some degree of breakage and ends as crispy and dry as the matted tresses of my nieces’ Barbie dolls.

Last year, I started hearing rumblings on TikTok about an ingredient in Olaplex causing fertility issues in animals, and a lawsuit alleging the product caused hair loss, scalp injury, blisters, and bald spots. It was hard to tell just how concerned I should be, but I noticed some salons stopped offering the treatment. The next time I got my roots done, however, my stylist told me about a new product that Sephora recently started selling, the K18 Molecular Repair Hair Mask. After that, I began seeing K18 products in every salon I visited, and every stylist who touched my hair sang its praises. Curious about this new miracle hair savior, I decided to visit the first U.S. hair salon that started using it on clients, Spoke and Weal in Manhattan. I spoke to hair cutter and educator Jake Seitchik about the mask and why it’s a must-have for anyone with chemically-treated hair.

How Does K18 Hair Mask Work?

I have no brain for biology, so I had Seitchik explain exactly why K18 is so revolutionary, especially compared with its competitors. He described that other products like Olaplex coat strands of hair like “shingles on a roof,” which creates inconsistencies in the strength of the hair. “If you have weak points and strong points, sometimes the hair ends up breaking,” he commented. K18, on the other hand, is able to penetrate the inner cortex of the hair and repair the polypeptide chains broken by chemical treatments. Rather than only improving how the hair looks and feels on the outside, it heals the actual cause of dryness and breakage.

Who Should Use K18 Hair Mask?

Seitchik recommends the K18 mask to anyone who has dyed their hair, used relaxers, received a perm or keratin treatment, or frequently heat styles. “Whenever we do a color treatment, we do K18 with it,” Seitchik explained. “Even with cuts, it's a nice refresh over chemical damage or heat damage; it just brings it closer to where your natural hair would've been had you not done these things.”

How do you use K18 Hair Mask?

Following any damaging treatments, Seitchik advises using the K18 mask during the following four washes, then once a week (or less) if needed. The mask itself is like none that I’ve ever used before: after shampooing (and before any conditioning) you work one pump of the product through your hair. Seitchik recommends emulsifying it by rubbing the cream in your hands before applying it so you can see it on your hair as you massage it in. Use one additional pump if needed (it’s important not to use too much or it won’t work correctly) and let it sit in your hair for four minutes. After four minutes, the mask has penetrated and you can use any conditioning products on top of it. You can even get right back into the shower and condition and rinse as normal.

Maraya at the salon before getting her first K18 treatment.

At the salon about to get my first K18 treatment.

Photos: Courtesy of Maraya Fisher

Maraya after a month of testing K18.

After a month of using K18 and bleaching my roots.

My Review

After my initial treatment at Spoke and Weal, I used K18 for about a month and a half, and I’ve definitely noticed results. Normally, the ends of my hair are wiry, and the strands crimp in random directions or snap off at random points—no more. Since I’ve started using K18, I’ve had my roots done and my blonde bumped up to Gwen Stefani level, and my hair is still soft and shiny. Seitchik noted that if used properly, K18 should simply restore your hair to its state before you damage it—including original curl or wave patterns disrupted by chemical processes. The product available to average consumers is the same product used in salons, so you get the same effect from home.

Part of the series:

We Tried It

You May Also Like