IF you’ve ever dreamed of having hair as sleek and silky as a celebrity’s, you may have seen one hair brand, in particular, pop up across social media recently. And that is K18 Hair.
In our K18 Hair review, we put the trending product through its paces.
With over 90 million views of the #k18hair on TikTok alone, many have shared how the brand’s products have completely transformed their dry, damaged hair.
After current It girl Sofia Richie Grainge, whose star-studded wedding hit the headlines for all the right reasons earlier this year, was announced as the new ambassador and face of K18 Hair soon thereafter, I was keen to see if the products would have a similar effect on my hair.
As someone who has never coloured their hair and tries to limit the amount of heat that is applied to it on a weekly basis, my hair isn’t as damaged as it could be. However, I do struggle with frizz and overall dryness, both of which leave my hair looking rather lacklustre.
My hair also has a natural curl to it and even though it is fine, I have a lot of it. All of these things combined have left me searching for a routine that deals with that dehydrated and frizzy appearance.
For the purposes of this review, I will be discussing the current range of K18 Hair products currently available to purchase in the UK;
- The Leave-In Molecular Repair Hair Mask, £12-70 – buy here
- The Molecular Repair Hair Oil, £65 – buy here
- The Peptide Prep PH Maintenance Shampoo, £39 – buy here
- The Peptide Prep Detox Shampoo, £39 – buy here
So, do they really work? I’ve put K18 Hair to the test to find out.
5
Overall rating: 4/5
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Pros:
- Results were visible from the very first use
- My hair felt considerably softer after each use
- My hair was shinier and had more of a sleekness to it
- The entire range is vegan and cruelty-free
Cons:
- Each product is quite expensive
- May not make as much of a difference on hair that isn’t frizzy or damaged
K18 Hair review: quick summary
I’ve tried K18 Hair over the course of a month and each time that I have used the Hair Mask in particular, my hair looked and felt softer, shinier and healthier. It also tamed my frizz, particularly when I blow-dried my hair.
The Hair Mask was the real standout product for me, while the Hair Oil was nice enough when used as a finishing product. However, the price tag of this oil was slightly off-putting. Both of the shampoos worked to cleanse my hair but didn’t blow me away quite like the Hair Mask did.
K18 Hair review: in-depth
- The Leave-In Molecular Repair Hair Mask, £12-70 – buy here
- The Molecular Repair Hair Oil, £65 – buy here
- The Peptide Prep PH Maintenance Shampoo, £39 – buy here
- The Peptide Prep Detox Shampoo, £39 – buy here
What is K18 Hair?
K18 Hair is a science-backed haircare brand, which originated in the United States. What makes it stand out from others on the market is its patented K18Peptide™.
‘Instead of temporarily restoring just one type of bond, K18’s biomimetic peptide mimics the molecular makeup of keratin to reinforce strength along the length and width of the hair fibre,’ according to the brand.
This peptide, which is included in every one of their products, works at the innermost layers to reverse hair damage from bleach, heat, colour and chemicals.
The entire range is vegan, as well as cruelty-free. And all four products are free of Parabens, Sulphates, Silicones, Phthalates, Sodium Chloride, artificial colours, Formaldehyde and Formaldehyde donors.
First impressions
From the very first application, my hair looked and felt considerably softer and was much easier to manage. I also noticed a lot less frizziness, both when I let my hair air dry naturally and when I blow-dried it.
It was also easier to comb through my damp hair after I applied the Hair Mask, with it being considerably less tangled than it usually is as soon as I step out of the shower.
Performance
5
Each of the shampoos cleaned my hair efficiently, with the Detox Shampoo being used only once a week, as directed on the back of the bottle. I tried each of the shampoos on two separate occasions and they both lathered nicely and cleaned my hair efficiently but neither blew me away. They performed similarly to other, less expensive, shampoos that I’ve tried in the past.
The product that I was the most keen to try out was the Hair Mask. And, thankfully, I was not disappointed. From the very first application, my hair didn’t feel weighed down or overly coated with product, but it immediately felt exceptionally soft. And where it really shone was when I used it before blow drying.
Normally when I dry my hair with a hairdryer I end up looking like Cousin It… after they’ve been dragged through a bush. I’m talking fluffy, frizzy, out-of-control hair that immediately needs to be straightened or styled with heat to get it in order. However, I was truly shocked by how manageable and shiny my hair was when I blow-dried it after using the Hair Mask alone. I had several people comment on how sleek and healthy my hair looked the following day and I did not feel the need or urge to apply any more heat to style it after blow drying. This is pretty much unheard of for me and my hair.
When I did leave my hair to air dry, there was some improvement to the amount of frizz on my natural curls and again, it was considerably softer and shinier than it usually looks and feels. My curly hair didn’t look as dehydrated as it normally does either, with it having a bit of a sheen to it.
To compare my hair in its natural curly state to when it was blow-dried, after using the Hair Mask, I preferred the way that it looked after it was blow-dried. While my curly hair was less frizzy, it did look slightly wet, even when it had dried fully. But this almost-wet-look to parts of my hair did give it a shiny appearance. Having both the mask and the oil in my hair also seemed to weigh some of my curls down but I did still appreciate that my curls felt a lot more nourished.
I tried the Hair Oil both on damp and dry hair and found that it had more of an impact as a finishing product on dry hair than it did on damp hair, where it was quite difficult to determine its effectiveness.
How to use K18 Hair
5
- The Leave-In Molecular Repair Hair Mask, £12-70 – buy here
- The Molecular Repair Hair Oil, £65 – buy here
- The Peptide Prep PH Maintenance Shampoo, £39 – buy here
- The Peptide Prep Detox Shampoo, £39 – buy here
Let’s start with the Hair Mask. Unlike traditional hair masks which tend to be applied liberally after you’ve shampooed and conditioned your hair, the K18 Hair Leave-In Molecular Repair Hair Mask is a little different.
After shampooing, either with the accompanying K18 Hair shampoos or your usual shampoo of choice, you do not add any other conditioning products, whether that be a traditional conditioner, a serum or a treatment. You take towel-dried hair and start with a single pump of the K18 Hair Mask. Depending on the length and thickness of your hair you may need two pumps or a pump and a half – I found that one pump worked well on my current length of hair.
Something else that makes it stand out from other hair masks that I’ve tried; the mask can be applied all over, instead of focusing solely on the ends. After you have towel-dried your hair, do not reach for your hair comb or Tangle Teezer. You don’t even want to use your fingers to break up any tangles or knots. Instead, you apply the K18 Hair Mask and let it sit for a total of four minutes. According to Jordan Alexander, Senior Director of Global Education at K18 Hair, ‘The primary reason for waiting for 4 minutes is that this is the amount of time needed for the peptide to be most effective. If someone were to use additional styling products before the 4 minutes is up, this could hinder the efficacy due to the presence of oil, silicones etc in other products.’
A little expert tip that the brand has shared online; when you add the pump or pumps of the mask to your hands, you’ll want to rub your hands together until you see the product turn white and coat both palms and all ten fingers. This makes it easier to see exactly where you’re applying the mask on your strands. And as the name may imply, you do not rinse this specific hair mask out.
5
The Molecular Repair Hair Oil can either be applied to damp hair once the allotted four minutes are up. Or you can apply it to dry hair as a finishing product.
Both of the shampoos work exactly as you would expect a shampoo to. First wet your hair, massage either of the shampoos into your hair and scalp and rinse thoroughly. You can repeat the process if necessary and as someone who double cleanses their hair, this is what I did.
Can you overuse K18 Hair?
- The Leave-In Molecular Repair Hair Mask, £12-70 – buy here
- The Molecular Repair Hair Oil, £65 – buy here
- The Peptide Prep PH Maintenance Shampoo, £39 – buy here
- The Peptide Prep Detox Shampoo, £39 – buy here
‘You can overuse K18 in the sense of applying too much product during a single application – our principle is less is more – however this is not damaging for the hair as the hair will only accept as much as it needs,’ Jordan revealed. ‘It may result in a heavy texture for the hair that requires rinsing.’
‘When it comes to the number of uses, K18 Hair cannot be overused as damage is ongoing be it chemical, environmental or thermal. We recommend using consistently for 4-6 washes consecutively and then as needed.’
I used the Hair Mask, in particular, after five successive washes, while I put the entire range to the test. Going forward I would be happy to use the Hair Mask once or twice a month, especially before important events or when I want my hair to look its best.
Is K18 Hair expensive?
At £30 for the 15ml size of the Hair Mask – or £12 for the 5ml trial size and £70 for the 50ml version – it’s certainly not the cheapest hair mask on the market. Other comparable bond repair masks tend to range from around £28 to £45 for at least 45ml of product, making K18 Hair’s almost double the price.
The Molecular Repair Hair Oil is also on the pricier side for hair oil. Typically hair oils range in price from around £20 to £35, making K18 Hair’s Hair Oil one of the most expensive.
The shampoos are £39 each, which is considerably more expensive than any shampoo that I’ve ever purchased in the past. And if you are on a budget and can only pick up one or two products from the K18 Hair range, you could quite easily search for alternative shampoos that also detox or pH balance your hair and scalp for less.
Where to buy K18 Hair
While K18 Hair has a range of professional products sold directly and exclusively to hair salons, the four products that I put to the test are the core range available for members of the public to buy here in the UK.
All four products are available from Space NK, Sephora UK and Cult Beauty, here in the UK, as well as on the UK K18 Hair website. All three retailers routinely offer discount codes, so if you’re looking to invest in a K18 Hair routine like I did, it may be worth looking for or waiting for a sale or discount code to make it more affordable. For example, if you haven’t placed an online order with Space NK or Cult Beauty before, using the code FIRST15 will take 15% off your order, which can be quite the saving if you plan on buying several of the K18 Hair products.
K18 Hair alternatives
These are just a few of the alternatives to the Hair Mask, Hair Oil and Peptide Prep Shampoos.
- Olaplex No.8 Bond Intense Moisture Mask, £28 from John Lewis & Partners – buy here
- Living Proof Triple Bond Complex, £42 from Space NK – buy here
- Olaplex No.7 Bonding Oil, £28 from Lookfantastic – buy here
- Virtue Healing Oil, £42 from Cult Beauty – buy here
- OUAI Detox Shampoo, £28 from Sephora UK – buy here
- Grow Gorgeous Balance pH-Balanced Shampoo, £14 from Lookfantastic – buy here
The verdict: does K18 Hair work?
As someone with dry, frizzy hair, K18 Hair has made a marked difference to how my hair looks and feels. I can easily see why stars such as Sofia Richie adore it as much as they do.
While all of the products in the range did what they claimed to, it is the hair mask that has really impressed me. I will be continuing to use it and the Hair Oil as part of my haircare routine. Both make my hair much easier to manage, have helped to calm down frizz and have even prolonged my hairstyles between washes.
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