Dear, Klairs is a Korean beauty brand by Wishtrend that emphasizes simple formulas at affordable prices with no harsh ingredients.
I'd describe the brand as a Korean version of The Ordinary (known for its budget products) with the style and aesthetic of Australia-based Aesop.
Among its collection, Klairs Freshly Juiced Vitamin Drop stands out as the No. 1 bestseller with over 1 million units sold (according to Wishtrend) and over 7,500 reviews.
Does this product live up to the huge hype and rave reviews?
Let's find out! ⭐
First of all, a good Vitamin C Serum should serve 3 main functions:
(source: The Roles of Vitamin C in Skin Health, 2017)
Second of all, there are 2 general types of Vitamin C:
(source: Stability, Transdermal Penetration, and Cutaneous Effects of Ascorbic Acid and its Derivatives, 2012)
In this case, Klairs uses 5% L-Ascorbic Acid at a pH level of 3.81 (source: Sokoglam).
This is considered a low concentration of Vitamin C and can be used as a booster by adding a few drops to your regular moisturizer or serum.
Research by Dr. Sheldon Pinnell, the founding scientist of SkinCeuticals, has demonstrated that L-Ascorbic Acid can only penetrate the skin at a pH level below 3.5 (source: Topical L-Ascorbic Acid: Percutaneous Absorption Studies, 2001).
This is due to a concept called Free Acid Value.
In short, more free acid forms of L-Ascorbic Acid are available at lower pH levels and this is a good thing because only the free acid form can penetrate your skin's oily barrier.
(for more information, check out LabMuffin's excellent guide)
At a pH of 3.81 (and with only 5% L-Ascorbic Acid), it's unlikely that you're going to get much Vitamin C into your skin, which means you won't get those amazing skin benefits that we discussed earlier (brightening, tightening, and antioxidant protection).
Dear, Klairs also included a few enhancers:
Overall, I give the ingredients a score of 2.5. (the low level of Vitamin C combined with a less-than-optimal pH level means you're unlikely to get much skin absorption)
When it comes to product design, I’m mainly focused on overall functionality and usability, although I do occasionally give bonus points for exceptional aesthetics.
For vitamin C serums, it’s important to protect the contents from light, air, and heat since vitamin C (especially LAA) naturally oxidizes over time and loses its potency.
Unfortunately, Klairs does not pass this test.
While its product design is indeed very aesthetic, the transparent dropper bottle simply does not effectively block out UV light or stop air (oxygen) from getting in.
This is a big problem as L-Ascorbic Acid is notorious for its stability issues (Klairs claims it uses a "Hybrid Stabilization Technology" but I didn't find any details about what this is).
You can keep this product in your fridge to help fend off oxidation and preserve potency.
The gold standard is an opaque container with a pump dispenser (ideally an airless one). Drunk Elephant C-Firma Day Serum and Clinique Dark Spot Corrector are prime examples of good product design in action.
Overall, I give the product design a score of 2.0. (does NOT prevent oxidation)
Klairs Vitamin C Serum has a clear liquid consistency that is easy to apply and feels kind of like a light oil when you spread it over your face.
Most people said the product was absorbed quickly and didn't cause any skin irritation.
There's a bit of a smell and warmness when you apply it but this goes away quickly.
Finally, if you have any allergies or sensitive skin, please note that there's trace amounts of orange peel oil and lavender oil present.
Overall, I give the texture & smell a score of 5.0. (easy to apply, no lingering smell)
Of course, the most important question is, does Klairs Vitamin C Serum actually work?
Given the problems that we identified earlier with the formulation (5% LAA at pH of 3.81) and product design (transparent dropper bottle), I was very surprised that the overall rating was a high 4.5+ even with over 7,500 reviews across multiple retailers.
The percentage of 5-star reviews is also extremely high:
Now, I know that Amazon has historically had a huge problem with fake reviews and sellers who engaged in rating manipulation. As CNBC explains in the video below, one of the telltale signs is an extremely high 5-star rating percentage:
On the other hand, the reviews were very positive across multiple merchants which would be harder for sellers to game. Most were genuine comments about the product like:
In addition, I take comfort in the fact that Yes Style has over 4,000 reviews and they only allow verified buyers to write reviews (unlike Amazon which allows everyone).
Overall, I give the results a score of 5.0. (very high ratings across multiple merchants)
Klairs Vitamin C Serum is one of the most affordable on the market.
It's a great way to incorporate a bit of Vitamin C into your regular skincare routine!
If you're a bargain hunter (like me), you might want to consider these gift sets that include Freshly Juiced Vitamin Drop along with popular Klairs products:
Overall, I give the price a score of 5.0. (it's super affordable!)
Finally, I’ve handpicked two customer reviews that I feel are fair and representative:
"I never used a vitamin c serum before so this is my first time. my skin looks so bright and beautiful just in about 1 or 2 weeks of using this in the morning with sunscreen and in the night (I am also using the I'm from rice toner). Keep this in a cool and dry place to avoid oxidization (I'm keeping this in my fridge). This is so gentle so its amazing if you are a beginner like me. After I finish this I wanted to try a stronger vitamin c serum but many people said that they receive same results from using this daily as to using a higher concentration vitamin c serum. This is going to be one of my holy grail."
Minus 2 stars for packaging: Vitamin C rapidly breaks down in light, and needs to be in an opaque airtight bottle, in a cool place. I wasn't able to get through half the bottle before it started oxidizing into an off-putting yellow color. The print also began rubbing off, which defeats the purpose of having instructions. Nowadays, there are many vitamin C serums/drops on the market, I recommend choosing a different brand with better packaging."