Glycolic Acid Is a Gold-Standard Ingredient for Strong, Shiny, Glass Hair—Here's Why
It's the one ingredient your hair routine is missing.
In the world of skincare, glycolic acid is one of the stars. The exfoliating acid is renowned for its ability to fade discoloration, smooth texture, clear clogged pores, and boost collagen production. Lately, though, it's been popping up as a featured ingredient in popular hair products.
Admittedly, this gave me pause. How could this exfoliating acid possibly benefit my hair? After seeing the latest glycolic acid-spiked haircare product come across my Instagram feed, I decided it was high time to take this question to an expert—Rick Wellman, Master Celebrity Colorist and Hairtylist at The Salon Project in NYC, to be exact.
I don't want to spoil it for you, but after asking him my burning questions, I'm convinced everyone needs to incorporate glycolic acid into their hair routine. It's proof that the "skinification" of the scalp and hair is still going strong, and there are real benefits to bringing facial-grade ingredients and techniques into one's haircare routine. Ahead, learn everything there is to know about how this formerly skin-specific ingredient can seriously level up your scalp and hair health.
Article continues belowWhat Is Glycolic Acid?
We've already established that glycolic acid is an exfoliating acid, but it's important to know that there are two categories of exfoliating acids—alpha-hydroxy acids (AHAs) and beta-hydroxy acids (BHAs). "Glycolic acid is an AHA made from sugarcane," Dermatologist Ife Rodney, MD, FAAD, of Eternal Dermatology and Aesthetics, previously told Who What Wear. "It is a popular active ingredient in skincare for its exfoliation properties."
How Does it Benefit the Hair?
"We are seeing some unusual TikTok ways glycolic acid is being used for scalp and hair treatments lately," Wellman says. "Our salon clients are asking, 'Is this for real and does it really work?' My short answer: It's both legit and trending." Wellman says glycolic acid loosens dead skin and improves moisture and elasticity, which is why it's an excellent ingredient to use in scalp-exfoliating and buildup-banishing products. Whether it's included in a purely chemical exfoliant or used in combination with a physical exfoliant (such as when it's added to a salt scrub), it can remove product buildup and return balance to the scalp and strands.
Outside of exfoliation, it boosts moisture in the scalp and hair and can even boost shine, both by strengthening the hair strands and smoothing the hair cuticle for a glossy, light-reflective finish. "[Glycolic acid] can remove excess oily scalp or flaking issues, while also giving hair that balanced moisture and strength combo we all love," Wellman says. "Consider it (when used properly) like a 'scalp facial,' especially when paired and applied with a certified 'head spa’ set up." Per client popularity, Wellman recently upgraded his entire shampoo room with reclining flat-bed chairs and waterfall rinsing sinks for a spa-like experience; it's further proof that we're in an era of "skinification" of scalp and hair health. Consumers are eager to level up their hair routines with facial-grade ingredients, treatments, and experiences—glycolic acid fits the bill.
How to Use Glycolic Acid for Scalp and Hair
Since there are now so many glycolic acid-spiked scalp and haircare products, it's easy to follow the best-use directions on the label. However, Wellman has a couple of important things to note. First, avoid using a glycolic acid exfoliating treatment on the scalp or hair more than once a month (twice at most.) "Here’s my reality check, speaking from experience: Dumping face-grade glycolic toners straight up weekly is not a good move. When misused and abused, it can actually weaken hair over time and create scalp barrier damage. Glycolic acid is not a hair growth treatment."
Second, avoid using high-strength glycolic acid treatments on sensitive scalps or directly after a hair color treatment. "I’ve seen it strip some color molecules," he says. That said, if it's used safely and correctly, he says glycolic acid can *truly* benefit the scalp and hair. "As you can see, there are ways to use glycolic acid properly for amazing benefits. So, my advice? Do your homework and don’t get hyped up on TikTok alone, especially when chemicals, your skin, and scalp are involved." Below, shop some of the best glycolic acid products.
The Best Glycolic Acid Scalp & Hair Products
"I recommend starting out lightly when considering glycolic acid for scalp and hair treatments with a more holistic approach such as Davines Naturaltech Detoxifying Scrub Shampoo finished with Davines Renewal Serum Superactive," Wellman says. "Those don’t rely on glycolic acid alone. Start there, then see and feel how your hair and scalp react."
"If you wish to go full force stronger, try The Inkey List's Glycolic Acid Exfoliating Scalp Scrub. Adding a simple 10-minute scalp massage at home or in salon will also help activate any glycolic and exfoliating ingredients as well!"
This derm-recommended exfoliating toner can be used to treat multiple skin and scalp concerns, including a flaky, oily scalp. Simply apply it straight to the scalp, let it sit for a few minutes, and shampoo as normal.
I've been testing this hair serum lately, and I'm obsessed. It's lightweight, hydrating, and makes my otherwise dull strands look healthy and glossy. Plus, it prevents frizz and fly aways, providing up to 14 times smoother hair.
This in-shower hair rinse uses glycolic acid to reduce frizz by up to 73%, even in high humidity. It takes 60 seconds to work, and the "glass hair" results last up to 72 hours. It's the epitome of a low-effort, yet high-impact product.
Drugstore shampoo can provide stellar results. This L'Oréal shampoo is proof. Its glycolic-acid formula whisks away sweat, oil, and product buildup, while boosting moisture and shine. I'm talking about glossy, expensive-looking strands.
Don't forget the matching conditioner.
Kérastase's Gloss Absolu line simply doesn't miss, and this high-shine styling cream is no exception. The do-it-all, glycolic acid-spiked formula smooths hair, protects heat up to 450°F, and lasts up to four days.
I also love this luxe hair mask. The creamy texture melts into the hair, providing lightweight moisture, bouncy volume, and a highly reflective finish.
This scalp scrub-shampoo hybrid uses both chemical (glycolic acid) and physical (salt crystals) exfoliants to detox the hair and scalp. Meanwhile, stimulating caffeine and rosemary extracts boost circulation and support healthy growth.
How We Chose
Beauty editor Kaitlyn McLintock has a decade of experience testing and reviewing beauty products. She curated this list of the best glycolic acid haircare products by consulting a hairstylist, polling her fellow Who What Wear editors, and testing products on her own hair. She also read real-world reviews. At the end of it all, she had a robust, deeply researched list.
Why Trust Us
At Who What Wear, we know that beauty isn't one-size-fits-all. Over the years, our editors have tested thousands of products—including skincare, makeup, haircare, and nails—while also working closely with trusted experts, like renowned dermatologists, celebrity makeup artists, and other leading industry insiders. Together, this ensures every guide is well-researched, inclusive, and relevant to you.
We focus on formulas that deliver, whether they're affordable favorites or luxury investments. Our product selection is based on tangible results, ingredient know-how, and what we'd truly recommend to our closest friends and family members.
