This $29 K18 Leave-In Hair Treatment Miraculously Saved My Strands After Severe Damage

Looking back to better days (i.e. my stress-induced hair color outburst). (Pictures: Katie McBroom)

Confession: Coloring my own hair impulsively was one of my COVID coping mechanisms. (So ​​if you catch me rapidly fluctuating from red to pink to orange and then back to blonde, I might be going through something.) Tldr; I destroyed my own hair even though I should know better as a longtime beauty writer with a cosmetology license. We’re talking about serious chemical damage and breakage, mostly from overuse of bleach. (I know, I know. It was a weird time, okay?) Please do as I say, not like I did back then.

Luckily for me and the wisps of straw left on my head, the colorist I usually go to, Rachel Bodt (who treats my hair much better than me), recommended the K18 Molecular Repair Hair Mask to get my mop back in shape. (Rachel also does Beyonce’s hairso it’s safe to say that I would trust him with my life.)

The K18 mask is a leave-in treatment for all hair types that clinically reverses damage in just four minutes. Patented peptide technology works on the deepest layer of hair, reconnecting polypeptide chains and Disulfide bonds broken during bleaching, chemical services and heat styling. This helps renew the strength and elasticity of the core, restoring smoothness and softness to the hair.

I can attest to this magic, but be sure to read the instructions (and/or listen to me) before using it. K18 is designed for application to damp hair after shampooing. Yes, that’s right, that means you skip the conditioner. It sounds crazy since we’ve been conditioned (ha!) to use both, but you want the mask to sink into the hair cuticle without any buildup getting in the way.

So, wash your hair, towel dry it thoroughly and add a pump of the mask, working it evenly from tips to roots. If you have very long, thick hair, you may need a little more, but it’s best to start with a small amount and evaluate. (I also like that you only need a little because a bottle lasts forever and makes the price less painful.) Let sit for four minutes (no rinsing!), then you can apply additional products and style as usual. The brand recommends using it for the first four to six washes, then as needed. Spoiler alert: I needed it. And the K18 delivered as promised.

Now you don’t have to believe me, but I bet you will after seeing the pictures. See the very dramatic results below. The photo on the left was taken before using the K18, the photo in the middle was taken after one month of use, and the last image on the right shows the results after four months. Each shows my hair after natural drying with no product in it (other than K18 in the “after” shots). I didn’t cut my hair during this time and my roots were only touched up once. For science.

Three photos of a person with blond hair

The epic resurrection of my hair thanks to the K18 leave-in mask. (Pictures: Katie McBroom)

Now if it can this it can definitely help with any damage you have on your head. In addition to chemical and coloring services, there are a multitude of reasons why your hair might need this molecular strengthening. Hot tools, exposure to the elements, certain products, showering with hard water, even aging (gasp!) can all contribute to damaged hair becoming dry, brittle and depressing.

Don’t get me wrong: I love Olaplex, too. Especially the professional additive and treatment (aka #1 and #2). For the love of all things sacred, if you get your hair stripped at the salon (ie: highlights, double process, balayage, or if the bleach touches your hair), please invest in these additional services if you can. Your colorist will know what I’m talking about.

A reason why I spring K18 instead of Olaplex’s consumer range, it’s because you can literally see results in four minutes. I also love that it’s leave on so it continues to strengthen your locks continuously. Still love and recommend using the OG take home treatment Olaplex No. 3 intermittently, but remember this is a shower mask designed to be washed off. So, these two beasts are different even though they have similar link building properties.

And yes, Olaplex offers leave too, but I like the K18 better. There, I said it.

If you have Amazon Premier, you will of course benefit from free delivery. Not a member yet? No problem. You can sign up for your 30 day free trial here. (And by the way, those who don’t have one Prime always get free shipping on orders of $25 or more.)

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David R. Brewer