We Tried the New Launch That Activates Incandescent Skin Now (and Long-Term)

Welcome to Deep Reviews—your one-stop destination to discover the absolute best products and brands the beauty industry has to offer. Every month, the Who What Wear staffers you already know and trust will research, test, and review the market's most sought-after and buzzed-about products to see which formulas (of the hundreds up for consideration) are truly worth your hard-earned money and attention. You can expect honest, completely uncensored feedback and no-BS recommendations our hard-to-please testers endorse without reservations. To put it simply, stick with us, and buyer's remorse will be a thing of the past.

The majority of our Deep Reviews will feature our editors' honest, ultra-hot takes on entire product categories or multiple products from a particular beauty brand, but every so often, we'll sprinkle in a special single-product format called Honestly, I Love It. As the name suggests, these reviews will hone in on a standout beauty formula our editors quite literally can't shut up about. This time around, we're doing a group format, and a few of my fellow beauty colleagues and I are sharing our honest feedback (plus pretty major before and after photos) re: a brand-new launch from one of our all-time favorite beauty brands, Kosas. Enter the Glow I.V. Vitamin-Infused Illuminating Skin Enhancer. 

If you've been here before, there's a good chance you already know that I'm wildly infatuated with pretty much anything Kosas makes, its famed Revealer Foundation and Concealer, in particular. (This glowing review of the former stands as proof.) In fact, pretty much every other complexion product I've tried post-Kosas has paled in comparison—not only do the products make my skin look great, but they're also loaded up with tons of clean ingredients that won't do your skin dirty in the long run. In fact, Kosas's range of products is designed to actually treat and improve your skin while you're wearing them, so you're getting a very satisfying dose of instant and long-term gratification. (I've even been known to fall asleep in the foundation and concealer. Although, it's bad beauty-editor etiquette to admit that kind of thing. I didn't say it!)

So when I heard that the brand was launching a brand-new skin-enhancing product—think one part highlighter, one part skin tint—I knew the Who What Wear beauty team had to give it a try. Since you can use it three different ways—all over, as a targeted highlighter, or mixed in with foundation or other skincare—I let my colleagues run wild and use it however they wanted to and in whichever way felt the most them. The good-to-know product details and our honest reviews are below. Keep scrolling!

As I mentioned above, Kosas Glow I.V. is designed to be a true multitasking formula that can moonlight as an allover sheer and shimmery base (one full pump), a highlighter (quarter of a pump), or radiance-encouraging mix-in (half pump) with your other favorite makeup and skincare products. Word to the wise—a little goes a long way!

It comes in 10 stunning shades, boasts 91% natural-origin ingredients, and is hypoallergenic, nonacnegenic, and safe for sensitive skin types. 

Glow I.V.'s hero trio of ingredients includes the brand's unique VitaGlow-D botanical complex for hydration, glutathione for brightness, and algae extracts (which are naturally rich in polysaccharides, peptides, and amino acids) for an extra shot of skin nourishment. 

What's really interesting about this product compared to similar items on the beauty market, however, are the long-term results of regularly wearing it. This isn't a *regular* skin tint; it's a *skincare-grade* skin tint! (Hopefully you heard that in Amy Poehler's Mean Girls voice.) Based on a consumer study of 33 women, Kosas reported that 100% of testers agreed that after four weeks of wearing Glow I.V. and the fan-favorite Revealer Foundation, their skin appeared healthier, brighter, and all-around more hydrated. And the clinical measurements, the findings demonstrated an increase in skin hydration by 150% and an increase in luminosity by 75%.

Main skin concerns:

I have dry skin, and lately I’ve been dealing with cystic acne around my chin. 

What were your hopes and dreams for the Kosas Glow I.V. before trying it?

I was hoping it would look something like when I apply Supergoop!'s Glowscreen but a little bit more blurred and a better match for my skin tone!

How did you apply it?

I applied it with my Chantecaille foundation brush. Instead of using foundation on top, I just applied concealer under my eyes and in any problem areas and blended that out with my fingers. 

What would you rate it from one to five and why?

Right after I applied it, I would have probably given it a 3.5. I thought it looked really pretty but maybe not necessary. My mind immediately changed, however, when I went to an actual Kosas event wearing it. All of my editor friends kept coming up to me and telling me how good my skin looked. I felt like an actual poster child for Kosas when I told them it was Glow I.V. The founder, Sheena Zadeh-Daly, complimented me before she even knew I was wearing Glow I.V. Anyway, after getting more compliments on my skin in the span of 20 minutes than I’ve ever gotten in my life, I am giving this product a five. 

Will you keep using it in your routine?

Yes, absolutely—like I said, I’ve never been more complimented in my life!

Would you recommend it to a friend?

Yes, I would recommend it to anyone who wants to look glowy and doesn’t wear full-coverage foundation, because I’m not sure how well it would translate underneath a full-coverage formula. 

What did you love and not love? 

I loved how it made my skin look. My only complaint was adding an extra step to my makeup routine—but I think it’s worth it. 

How does it compare to similar products you’ve tried?

It does remind me an awful lot of Glowscreen sans SPF but with a wider shade range. It also reminds me of the Fenty Eaze Drop'lit All-Over Glow Enhancer.

Shop Katie's Look

Main skin concerns:

My main skin concerns are dry/dull skin during the winter months and dark spots. I love any product that can take on my "problem areas” while giving me a ton of glow.

What were your hopes and dreams for the Kosas Glow I.V. before trying it?

I was hoping that the skin enhancer would work as a combo light foundation, so I used Revitalize as my shade. I was after even, glowy skin with a little bit of coverage.

How did you apply it?

I decided to apply it just like I would apply any other base by first putting some product on the back of my hand, and then applying it with a Beautyblender. I realized pretty quickly that I didn’t need too much of the product for the coverage I wanted.

What would you rate it from one to five and why?

My rating would be a five. Overall, the product feels super hydrating on my skin and doesn’t leave any splotchy areas. It also works really well with my other go-to products (a liquid highlighter and cream blush).

Will you keep using it in your routine?

Yes, I will definitely keep using this product in my routine. This is one of the first Kosas products that I’ve used, and I was definitely surprised by how glowy and smooth my skin looked. I think it will become one of my favorite products to use for the no-makeup makeup looks I’m obsessed with.

Would you recommend it to a friend? 

Yes, I would recommend this product to a friend because it’s a great price point for something that multitasks, and it does exactly what it promises to do as a makeup product.

What did you love and not love?

My favorite thing about the product was how smoothly it went onto the skin. My least favorite thing about it was maybe how much actually comes out of its tube with a single pump. Less is definitely more for this product!

How does this product compare to other similar products you’ve tried?

Similar to Rose Inc’s Luminous Skin Tint Serum and Saie’s Glowy Super Gel, Kosas’s Glow I.V. Vitamin-Infused Skin Enhancer does a great job of making the skin glowy and hydrated while also offering some coverage for lighter makeup days.

Shop Maya's Look

Main skin concerns:

Dullness, dryness, uneven skin tone, some pigmentation (thank you, L.A. sun!) and acne scars.

What were your hopes and dreams for the Kosas Glow I.V. before trying it?

Even though this product can be used multiple ways, I wanted it to be a magical skin elixir that would make my no-base makeup days (aka when I’m running wild around town without foundation and concealer) a little more glowy. I wanted something that would help even out some of the redness and pigmentation in my skin without looking like I was wearing any type of makeup. My skin has also been especially dry and dull this winter, so I was dreaming of an instant injection of brightness and light-catching glow. 

How did you apply it?

I mixed it in with a barrier-protecting ceramide-rich serum I’ve been loving and applied it straight-up with my hands. I had also applied a little bit of eye cream, under-eye brightener, and chapstick.

What would you rate it from one to five and why?

I would give this a four! Just like the name suggests, I did feel like my complexion got an instant shot of glowy radiance. My skin looked brighter, slightly more even (a V red acne scar by my lip looked less noticeable), and all around more hydrated and bouncy. Not surprising considering the amazing, vitamin-inspired ingredients. The only thing that is stopping this from getting a full five out of five for me is the fact that when the light hits just so, it is pretty shimmery. I personally liked the glazed-doughnut effect it gave my skin, but it does lean a tad Edward Cullen. That said, because it is tinted, it looks less blatantly sparkly. Now that I’ve tried it, I’ll definitely use the bronzy shades all over my chest and shoulders (so pretty) and will continue to mix the lighter shades in with my skincare on no-makeup days. (I kind of feel like it might be too much added in with other makeup products like foundation, but that’s just me!) I’ll definitely keep testing it as a highlighter just on certain areas of my face, like my cheekbones, brow bones, and Cupid’s bow, as well. Also, fair warning, a little goes a long way! This tube will last you longer than you think it will.

Will you keep using it in your routine?

Yes! It instantly took my skin from The Walking Dead to alive and bright and radiant. 

Would you recommend it product to a friend? 

Yes, I think it’s a great clean, multitasking product. People can really customize how they want to use it, and I think it looks really beautiful on the skin.

What did you love and not love?

My favorite thing was how instantly it transformed the look and feel of my skin. Least favorite would probably be that it’s pretty concentrated in the shimmer department, but now that I know that, I’ll be able to adjust my application accordingly.

How does this product compare similar products you’ve tried?

Def more shimmery! But it didn’t feel oily or slick on my skin, and it actually has skin-improving ingredients like glutathione, algae extracts, and the brand’s special botanical complex called Vitaglow-D. It's by far one of the best skin-enhancing complexion products I've tried, and I've tried lots.

Shop Erin's Look

Main skin concerns:

Dullness, uneven skin tone, redness.

What were your hopes and dreams for the Kosas Glow I.V. before trying it? 

No matter the time of year, I’m a sucker for some glow. I was really hoping this would inject some much-needed life into my dull-looking winter complexion. 

How did you apply it?

I’m a self-proclaimed lazy makeup wearer and always looking for ways to cut my getting-ready time, so I kept things really simple. After my skincare routine, I used my hands to apply a layer over my skin. Honestly, hands and fingers are the most underrated makeup tools ever. 

What would you rate it from one to five and why?

I’d give it a four. I really like the simplicity of the formula and how it instantly brightened up my complexion. But I need to play around with it a little more to try and minimize the amount of glitter. The glitter was just a little too much for me, but I feel like mixing it with my morning moisturizer might help tone it down a bit.

Will you keep using it in your routine?

Yes! I can see myself grabbing for this on weekends when I want to wear something more than nothing but not as much as my typical tinted moisturizer. It’s the perfect in-between—something even easier than my typical tinted moisturizer. 

Would you recommend it to a friend? 

Yes! I’d tell them that the beauty of this product is that it’s so versatile and they can use it in whatever way makes sense with their routine. If they’re lazy with makeup (like me), they can wear it on its own, or they can mix it with their favorite foundation for an extra glowy boost. Just don’t expect to cover up any major blemishes or spots. 

What did you love and not love?

I love when makeup doesn’t feel like, well, makeup, and this skin enhancer felt like I was wearing absolutely nothing on my skin. But after applying it, there was an abnormal amount of glitter layered over the palms of my hands—and then my clothes!—for the remainder of the day. I wasn’t really into that. 

How does it compare to other similar products you’ve tried?

I’d say it’s pretty comparable if not slightly better than others I’ve tried. Other formulas either get dry and separate under my nose and above my brows or straight up make my skin pill, which is absolutely not okay in my book.

Shop Caitie's Look

Main skin concerns: Redness and pigmentation (plus some dullness).

What were your hopes and dreams for the Kosas Glow I.V. before trying it?

I hoped my skin would look bright and blurred, like when you try a beauty filter on TikTok. (A girl can dream, right?)

How did you apply it?

I have slightly oily skin in my T-zone, so I applied it like a highlighter—patting it on my cheekbones, nose, Cupid’s bow, and brow bones using a Beautyblender.

What would you rate it from one to five and why?

I would rate it a four as a highlighter and a three as an overall base. I tried it both ways, and I found that when I used it as a highlighter, it gave my skin a lovely, natural-looking glow. When I used it all over, under my foundation as a base, it looked a little too shiny for my taste (but like I said, my skin veers on the oilier side).

Will you keep using it in your routine?

Yes! I’ll continue to use it as a highlighter.

Would you recommend it to a friend?

I would recommend this product to a friend if they struggle with dryness and dullness and they’re looking to dial up their glow. 

What did you love and what did you not love?

My favorite thing about this product was the creamy, blendable texture, which made it easy to pat into my skin for the most natural-looking result. My least favorite thing about this product was the ultra-fine glitter particles that are suspended in the formula. They look great in low light, but I found them to be a little too sparkly for my taste when I was in direct sunlight. 

How does this product compare to other similar products you’ve tried?

I would say it’s comparable to other, similar products. However, the fact that it’s formulated with good-for-skin ingredients gives it a leg up in my opinion. 

Is there anything else you would like to add?

If your main concern is dullness and dryness, this product will probably be your new fave. If you have oily skin, I think it’s better off being used as a traditional highlighter. 

Shop Kaitlyn's Look

Up next, This Brand-New Mask Resurfaces Your Face in Minutes—so My Face Played Guinea Pig