Kiehl’s Vitamin C Serum Gave Me Smooth, Even Skin in a Few Weeks—No Joke

Kiehl’s Powerful-Strength Line-Reducing Concentrate did an excellent job of visibly reducing fine lines and wrinkles and brighten and smooth my skin with little to no irritation, thanks to its high-quality ingredients.

We put Kiehl’s Powerful-Strength Line-Reducing Concentrate to the test after receiving a complimentary sample from the brand. Keep reading for our full product review.

I’ve been a big fan of retinol for about five years but wasn’t necessarily crazy about some of the side effects that came with it, like tight, dry skin and constantly worrying about getting a sunburn. When I got pregnant in early 2019, I was forced to part ways with my retinol, as it’s not recommended for pregnant women.

While I was bummed out at the prospect of no longer using a product that promised to keep my skin glowy and prevent wrinkles, the fact that pregnant women aren’t supposed to use retinol felt like a bit of a red flag. Should I be using it in my normal life if it was so dangerous for pregnant women? Once my daughter was born and I was breastfeeding, retinol wasn’t an option either—so I just kind of forgot about it.

But when I came across Kiehl’s Powerful-Strength Line-Reducing Concentrate, which contains high amounts of vitamin C along with hyaluronic acid, I was curious to see if this product could get the job done as easily as retinol.

Here’s how it panned out. 

kiehl’s powerful strength line reducing concentrate

Best for: Anyone looking to give their skin a little lift without toxic ingredients; works for normal skin.

Uses: Brightens and smoothes skin, reduces the appearance of wrinkles and fine lines

Potential Allergens: Made with vitamin C and hyaluronic acid, an allergic reaction is unlikely but always check with your dermatologist if you’re concerned.

Active Ingredients: Pure vitamin C (10%), ascorbyl glucoside, hyaluronic acid

Price: $70

About the Brand: Kiehl’s Skincare has been around since the 1850s, always with the promise of delivering healthy, high-quality, no-frills skincare products. 

About My Skin: Fair, freckly, and a little bit acne-prone

I have light skin that tends to get freckly in the summer, so sun protection has always been a must for me. I’ve also had acne on and off since I was a teenager—I thought I’d cleared it up for good when I was 27, but while I was breastfeeding it came back with a vengeance, although it seems to have cleared up again since I stopped. The combination of my fair skin and history with acne has left me with quite a few dark spots on my face, which I’m not the biggest fan of. 

At 34, so far my skin hasn’t gotten too wrinkly, but I do have some lines popping up around my mouth that I’m working hard to keep under control. 

The Feel: Light and lotion-like

I’ve mostly used vitamin C products in the form of a serum, so I was surprised to find that Kiehl’s Powerful-Strength Line-Reducing Concentrate was more of a lotion texture.

It doesn’t add any heaviness or stickiness when you apply it, but it’s one of those products where a little goes a long way.

Byrdie / Leigh Weingus

And the bottle made it easy to dispense a little more than I needed. 

Drying and Irritation: A little bit irritating, but it doesn’t last 

I’ve definitely experienced my fair share of irritation from skincare products like retinol, which have left me with this tight, dry stinging feeling. The first time I used Kiehl’s Powerful-Strength Line-Reducing Concentrate it didn’t bother me at all, but as time went on and I continued to use it morning and night as directed, I noticed more irritation happen in the form of a bit of a sting when I put it on. 

Byrdie / Leigh Weingus

The good news is that it doesn’t last. Unlike with retinol where my face would sometimes feel dry and irritated all day, the irritation only happened when I first put the Kiehl’s Powerful-Strength Line-Reducing Concentrate on. If your skin gets irritated easily, though, you may want to steer clear of this one. 

The Results: Brighter and smoother, as promised

Before writing this review, I spent two weeks testing the Kiehl’s Powerful-Strength Line-Reducing Concentrate both morning and night after cleansing and before moisturizing.

While I can’t say I saw my fine lines disappear immediately, within a week I noticed that my skin was more radiant and that some of my dark spots had gotten a bit duller.

My skin looked smoother overall, and when I touched it felt softer and more even—no annoying rough patches.

I’m hopeful that using this over time will reduce the appearance of fine lines and wrinkles, and hopefully prevent more from popping up. Thanks to the lack of irritation and early results on my skin, there’s no way I’ll stop using it.

Byrdie / Leigh Weingus

The Value: Expensive, both worth it

Retailing at around $70, the Kiehl’s’ Powerful-Strength Line-Reducing Concentrate isn’t cheap. But if you’re looking for a really high-quality product that will keep your skin in tip-top condition, this is it.

Byrdie / Leigh Weingus

Similar Products: You’d be hard-pressed to find a product that works this well

Drunk Elephant C-Firma Day Serum ($78): This is the only other vitamin C product I’ve ever tried, and I wasn’t a fan. While I like Drunk Elephant as a brand, the C-Firma Day Serum left my skin feeling sticky and I didn’t see much of a result in terms of the overall look of my skin. 

Sunday Riley LUNA Sleeping Night Oil ($55): It doesn’t have the same ingredients as Kiehl’s Powerful-Strength Line-Reducing Concentrate, but it has a similar promise of reducing the appearance of fine lines for a brighter complexion. Retailing at $55, Sunday Riley’s LUNA Sleeping Night Oil is cheaper than the Kiehl’s serum but it gave me similar results with more irritation and ingredients I was warier of. 

Final Verdict

If you’re looking to brighten and smooth with the help of some pretty great ingredients, Kiehl’s Powerful-Strength Line-Reducing Concentrate is the product for you.