"Does the K18 molecular repair range actually fix damage? Here's our honest review"
Bond-building hair treatments are everywhere you look nowadays. While we all used to strive to get the perfect balayage or nail the messy bun, all of our hair goals have pivoted towards healthy, glass-like strands (well, as close as we can get to that, anyway). Enter: K18.
The molecular repair range – in particular, the K18 Leave-in Molecular Repair Hair Mask (from £30) – has gone viral on social media for its damage-repairing powers, so much so that Hailey Bieber is reportedly a fan, as well as Sofia Richie Grainge. With this in mind, we, naturally, thought it was worth putting it through the biggest test of them all: trying to give two writer's frazzled, damaged, coloured locks a new lease of life.
So, if you've been wondering if the K18 haircare range is really worth the hype (and money), keep scrolling.
Does K18 actually work?
Even some of the best 'damage repair' hair ranges out there has only been a temporary fix for our strands, so we were intrigued by K18's long-lasting repair claims.
"K18PEPTIDE™ is in all our products and is an incredible peptide that can reverse damage at a molecular level in the polypeptide chain, renewing strength and elasticity on all hair types," explains Jordan Alexander, Senior Director of Global Education at K18.
Yep, that's right, you can use K18 products on all hair types, textures and colours (even if you're a bottle redhead like our guinea pig, Charlotte).
Is K18 better than Olaplex?
We've tried a lot of hair-bonding treatments out there and have never found Olaplex did quite enough for me, so would K18 be different?
"Our K18PEPTIDE™ – a unique amino acid sequence – works on a molecular level to restore hair back to like-new strength," says Alexander. "By reaching the innermost layers of hair and reconnecting broken keratin chains (the result of bleaching, chemical services, and heat damage) the peptide provides lasting renewal instead of temporarily patching damage like other bond-building products on the market," he adds.
Both brands work at a molecular level to rebuild the hair internally, however, arguably, K18 penetrates the innermost layers of hair to reach the core polypeptide chains (keratin chains) and fix those that are broken.
Spoiler: Both testers, Charlotte and Lia found it worked better than you-know-who, and the results weren't just flushed down the drain in the next wash (whether they were using K18 products or not).
How to use K18
The first mistake you can make with this range is using it like your normal haircare range. In fact, having your phone at the side of the shower just to make sure you get it exactly right may be a good shout... risky but necessary.
Here's a guide on how to use the K18 range for the first time:
How to use the K18 Peptide Prep Detox Shampoo...
For your first time using K18, wash twice with the K18 Detox Shampoo. Do not use conditioner. Get out of the shower and gently towel dry your hair, removing most of the moisture. Do not brush, instead separate hair gently with hands/fingers.
How to use the K18 Leave-in Molecular Repair Hair Mask...
Depending on length and thickness, use one or two pumps of the K18 Leave-In Molecular Repair Mask into your hands, remember less is more. If using the 15ml bottle, three to four. Spend time working the product into a thick white paste. Do not apply to hair until it is at this consistency. Start at the ends and pat the white paste onto the hair and then work up to the mids and roots. Do not brush and leave for 4 mins. Once time is up, brush your hair through.
How to use the K18 Molecular Repair Hair Oil...
Now to the oil. Less is more (K18 really emphasises this, to the point where it scared me). Use 2-3 drops of the K18 Molecular Repair Hair Oil on wet hair. Once hair is brushed through, work 2-3 drops of oil into your hands and then pat onto ends and work up to mid-length and roots.
And yes, K18 says you can use this regime every day if you're a daily hair-washer (although, it might be pricey).
"For optimal results, we recommend using the full K18 at-home damage repair routine (detox shampoo > mask > oil) for 4-6 consecutive washes and then you can reduce use to once every 3-4 washes (as needed) to maintain hair strength," says Alexander.
What is the K18REPAIR™ in-salon service?
Fully-fledged hair routines can be expensive to maintain, there's no doubt about it (hi, hello cozzie livs!). So, before investing in the above routine (before she's even finished her current shampoo and conditioner duo), Lia headed into the Hadley Yates Covent Garden salon in London to trial the professional K18REPAIR 2-step salon-exclusive service. (Unfortunately, the following K18REPAIR products aren't available for consumer purchase.)
Although it is a splashing the cash typ'a'treatment (IDK about you but I don't head down to the hair salon very often), if you are in need of a cut, colour or styling service, it's always worth going that extra mile for a deep conditioning repair with K18. You can find the closest in-salon K18REPAIR to you, here.
But before making it to the shampoo bowl for a wash with the K18 DAMAGE SHIELD pH protective shampoo, your stylist will start off by saturating the hair with the professional molecular repair hair mist and the peptide prep pro chelating hair complex. This chemical service works in just four minutes. Impressive, much?!
Together the spray-on products work to strengthen strands and effectively reduce seven of the most common types of metals and minerals. FYI, if you live in a hard water area such as London, this is a once in a few months essential.
The result? Better, more even colour, revived vibrancy, restored smoothness and bounce and improved effectiveness of products and styling.
The professional molecular repair hair mask is then to be applied for another four minutes before washing it all away and finally, styling with heat. Lia had the option to add a few drops of oil to the ends but due to the fine texture and short length of her hair, hairstylist Eric Vaughn deemed it not necessary.
Is K18 worth the hype?
We're glad you asked because this is what we're here for. Charlotte put the hair-bonding treatment range to the test with her coloured, wavy and fairly damaged hair to see if it actually improved its condition and texture.
Here's her honest review...
Our at-home K18 review
Due to the (what we think of as) very specific instructions of this range, it the routine can be easily f*cked up – not a great start. Once her hair was damp, Charlotte went to apply the shampoo. Now, warning: the detox shampoo is as black as our souls and like no shampoo we've ever encountered. Weird, to say the least, but you've been warned.
"I'd never usually wash my dry hair twice, but I'm a teacher's pet and followed their instructions (even though my hair was so knotty afterwards I cringed)," Charlotte says.
Next up came the famous K18 mask. "I know it said only 2-3 pumps, but this wasn't enough to cover my long-ish lengths, so I added another pump for good measure," Charlotte admits. "I was intrigued at how this was going to repair my strands in just four mins; usually, I leave my hair mask on for All Too Well (10-minute version) but this was aiming to repair in the same amount of time as the OG song length (both Taylor's Version, obvs).
"To finish off, I applied three drops of the oil. Again, my hair needs a 20p-sized amount of oil, so I did add a bit more than advised. It's not got a greasy texture like most hair oils I've tried, which was surprising."
The final result
If this was the result after just one wash, sign us up! "This was my hair after applying just the three K18 products, which is way more streamlined than my usual routine," Chalotte says. "It's clear to see just how much shinier my hair was, as well as a reduction in frizz. Plus, my hair colour looked way more vibrant. It's a yes from me.
"However, due to the lack of styling products used, my hair did get fluffier than normal once I went out into the wild (read: around central London). Overall, my hair was softer and shinier for days after, with no bedhead-induced matting at the back of the head to be seen."
As with everything, this review comes with one caveat. "My only comment is that, while they warn you that less is more, I don't think this can be said for all hair types and textures (like they claim to serve)," Charlotte says, before adding: "How much product your hair needs depends on its porosity, so I think the brand should acknowledge this a bit more. If you have thin pin-straight hair, sure, be careful, but if you have curlier hair than me, be prepared to use a bit more."
As with most haircare ranges, if you're the latter, you will get through these products quickly, which means it's going to be quite spenny. However, we definitely think it's worth starting a healthy hair journey with this range – there's no debating the glossy results.
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