Shop editor-loved Korean haircare brand Dr. Groot, now at Costco

Let’s talk about something that doesn’t always get the spotlight it deserves: haircare. And not just any haircare — Korean haircare.

Sure, we all know Korean skincare is basically the holy grail, but trust me, K-beauty has been holding out on us when it comes to hair. Until now. Because drumroll please: Dr. Groot, Korea’s No. 1 hair thickening brand is officially making its grand entrance into Costco stores nationwide this month.

I’m not just hyped because it’s new. I’m hyped because I’ve been using Dr. Groot for a while now, and it has completely transformed my hair game.

Korean skincare walked, so Korean haircare could grow — fast.

Let’s start from the top…literally. Korean skincare has earned its reputation with layers of hydration, glow-enhancing essences, and science-backed formulas. But when it comes to hair, Korean brands have been keeping their secret weapons close to the scalp. Enter: Dr. Groot. It’s already sold over 40 million units worldwide, which is a casual way of saying, “We’re kind of a big deal.” And now, for the first time, we’re getting it in bulk-sized glory at Costco (because yes, this is the kind of thing you do want to stock up on).

The best part? Dr. Groot isn’t just about looking good, though your hair will definitely be out here living its best voluminous life. It’s about scalp health, which is honestly the unsung hero of great hair. I didn’t always think about my scalp. I mean, it’s just… under there, doing its thing, right?

Wrong. Your scalp is the soil, and your hair is the garden. If you want lush, thriving locks, you’d better start tending to the roots, literally and figuratively.

After traveling to South Korea to learn the inside scoop about Korean haircare, I was floored that this isn’t as big of a conversation topic. Dr. Groot takes this to a science-fiction level (except it’s real science). The brand is a powerhouse collaboration between Korean scientists and dermatologists who have spent over 50 years researching hair and scalp issues.

FYI: these are not your average shampoo-makers. They’ve developed proprietary technologies that remove harmful microbes from your hair follicles and replenish beneficial ones — yes, prebiotics, probiotics and postbiotics all working in harmony to restore your scalp’s microbiome. Like a kombucha cleanse, but for your hair.

And let me tell you: the results are wild. In clinical trials, users saw an 82.2% reduction in hair loss due to breakage in just 2 weeks. That’s not a typo. That’s two weeks from brittle breakage to, “Oh hey, who’s your new hair stylist?” (Spoiler: It’s science.)

Now, let’s get into the hero product hitting Costco shelves: the Dr. Groot Scalp Revitalizing Solution Hair Thickening Shampoo. This comes in a super-convenient two-pack for $54.99, which is honestly a steal when you consider what’s inside. The formula is loaded with biotin, rosemary, and caffeine, basically a trifecta green smoothie for your scalp.

These ingredients exfoliate dead skin, hydrate deeply (scalp hydration improved by 169% in two weeks —again, not a typo), and boost circulation to your hair follicles to encourage new growth and stronger strands. You can actually feel it working, and I’m a case study.

After using Dr. Groot religiously for years now, it’s that product that’ll make your jaw drop in the shower. From silky smooth strands to blowout perfection, I seriously never want to run out.

Thank 👏 goodness 👏 for 👏 my 👏 Costco 👏 membership.

Here’s the thing I really love, though: this isn’t a beauty brand that just jumped on a trend. Dr. Groot isn’t here for the aesthetic alone (although, let’s be real, that packaging is so sleek it should be on display). It’s rooted in decades of clinical research, which is something I appreciate as a full-time beauty tester, shopping reporter and consumer.

Since I started using Dr. Groot, my hair has gone from “meh” to “how is your ponytail so full?” I’ve noticed less shedding in the shower, my roots are more lifted and my scalp just feels cleaner — like I gave it a facial. It’s like my hair woke up, drank a green juice, did a few sun salutations and said, “locks, let’s grow.”

And, let’s not ignore the joy of discovering something before it becomes the next big thing. Korean skincare had its moment, and now it’s time for Korean haircare to rise. Dr. Groot is leading that charge, and trust me, once your friends see your before-and-after, they’ll be begging you to let them in on the secret. You’ll be able to say, “Oh yeah, I picked it up at Costco,” with the kind of casual coolness usually reserved for insider fashion finds.

So yeah, big things are happening in the hair world. Dr. Groot has officially made the leap from cult Korean favorite to U.S. must-have, and I couldn’t be more thrilled. If you’ve been struggling with thinning hair, dryness, or just feel like your scalp has been ignored for too long, this is your sign. Head to Costco (online!), grab the two-pack and let science do its thing. And prepare to have people ask, “Did you get extensions?“

Because, no. That’s just the magic of Dr. Groot.

This article was written by Victoria McDonnell, New York Post Commerce Journalist & Content Strategist, who has spent countless hours researching, testing hundreds of products and comparing the latest makeup, skincare, hair and beauty items and trends to determine what’s truly worth your hard-earned cash. She evaluates formulas, textures, ingredients and more, in addition to consulting medical and industry experts. Some of Victoria’s latest conquests include testing the best vitamin C serums on the market, and a rinse-and-repeat review of the best shampoos of 2025. Victoria, who received a beauty industry essentials certification from the Fashion Institute of Technology, has been creating shopping guides for the New York Post since 2021 and previously held positions at Insider Reviews and CNN Underscored.