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This $29 K18 leave-in hair treatment miraculously saved my strands after severe damage
Confession: Impulsively coloring my own hair 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 again, I might be going through something.) Tldr; I wrecked my own hair even though I should know better as a longtime beauty writer with a cosmetology license. We’re talking severe chemical damage and breakage, mostly from the overuse of bleach. (I know, I know. It was a weird time, ok?) Please do as I say, not as I did back then.
Lucky for me and the straw-like strands left on my head, the colorist I usually go to, Rachel Bodt (who treats my hair much better than I did), recommended the K18 Molecular Repair Hair Mask to get my mop back in shape. (Rachel also does Beyoncé’s hair, so it’s safe to say I’d trust her with my life.)
The K18 mask is a leave-in treatment for all hair types that clinically reverses damage in just four minutes. The patented peptide technology works at the innermost layer of hair, reconnecting polypeptide chains and disulfide bonds broken during bleaching, chemical services, and heat styling. This allows core strength and elasticity to be renewed, restoring softness and smoothness to the hair.
I can attest to this magic, but be sure to read the instructions (and/or listen to me) before you use it. K18 is designed for application on 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 penetrate the cuticle of the hair without any buildup preventing it from doing so.
So, wash your hair, towel-dry it thoroughly, and add one pump of the mask, working it in evenly from ends to roots. If you have super long, thick hair, you might need a little more, but it's better to start with a small amount and evaluate. (I also love that you only need a little because one bottle lasts forever and makes the price tag less painful.) Let it 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. And the K18 delivered as promised.
Now, you don't have to believe me, but I bet you will after you see the photos. See the very dramatic results below. The photo on the left was taken before using the K18, the middle photo was taken after one month of use, and the last image on the right showcases results after four months. Each one shows my hair after drying naturally without product in it (other than K18 in the "after" shots). I didn't cut my hair during this period and only had my roots touched up once. For science.
Now, if it can do that it can definitely help with whatever damage you have on your head. In addition to chemical and coloring services, there are a multitude of reasons why your hair might need some of this molecular reinforcement. Hot tools, exposure to the elements, certain products, showering with hard water, even (gasp!) aging can all contribute to dry, brittle, depressing damaged hair.
Don’t get me wrong: I like Olaplex, too. Especially the professional additive and treatment (aka No. 1 and No. 2). For the love of all that is holy, if you get your hair lifted at the salon (meaning: highlights, a double process, balayage, or if bleach is touching your hair at all), please invest in these extra services if you can. Your colorist will know what I’m talking about.
One reason I’m gushing about K18 instead of Olaplex's consumer line is because you can literally see results in four minutes. I also love that it’s a leave-in, so it continues to strengthen your strands on an ongoing basis. I do still adore and recommend using the OG take-home treatment Olaplex No. 3 intermittently, but remember that this is an in-shower mask designed to be washed off. So, these two are different beasts even though they have similar bond-building properties.
And yes, Olaplex does offer a leave-in as well, but I like the K18 better. There, I said it.
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