In today's episode of "things you never expected to see on TikTok": People swiping glycolic acid (yes, the chemical exfoliant found in a slew of skin-care products) under their arms in place of deodorant. Apparently, the acne-busting acid can also stop sweat, beat body odor, and minimize pigmentation — at least according to the beauty enthusiasts and GA groupies on the 'Tok. And judging by the fact that the tag #glycolicacidasdeodorant has amassed an impressive 1.5 million views on the platform, plenty of people seem passionate about their pits and GA's (supposed) BO-blocking abilities. While some might assume that the views don't lie, others (🙋♀️) can't help but wonder if it's even safe to slather the acid on such sensitive skin — not to mention whether or not it actually works. Ahead, experts weigh in on the latest TikTok beauty trend.
What Is Glycolic Acid, Again?
Glad you asked. GA is an alpha hydroxy acid — aka a chemical exfoliator — derived from sugarcane. It stands out amongst all the other AHAs (i.e. azelaic acid) for its small molecular structure that makes penetrating the skin easy, which, in turn, allows GA to be so effective, Kenneth Howe, M.D., a dermatologist at New York City's Wexler Dermatology, previously told Shape.
Effective at what, you ask? Breaking down the bonds between dead skin cells to gently resurface the top layer of the skin and promote cell turnover, board-certified dermatologist and Mohs surgeon, Dendy Engelman, M.D. In other words, GA does an A job exfoliating the skin to leave users with a more even, radiant complexion. It also acts as a humectant, helping to keep skin moisturized, and an anti-aging ingredient. (See more: Here's Everything You Need to Know About Glycolic Acid)
Is It Safe to Use Glycolic Acid as Deodorant?
In general, GA safe to use on the skin — after all, it is included in a plethora of popular skin-care products. But, remember, it's still an acid and can cause irritation, especially on sensitive skin and/or if it's overused, say, daily as a deodorant, explains Dr. Engleman. "The underarm area can be sensitive, especially after shaving or waxing, so applying glycolic acid daily as a 'deodorant' may cause discomfort and irritation," she says.
So why are so many people swooning over it on the 'Tok? Largely because of GA's ability to block BO — so much so that one TikTok user now "smell[s] so clean" even after hitting the gym. "I still sweat," she says. "But there's absolutely no odor."
So, Does Glycolic Acid Actually Work as Deodorant?
GA may temporarily lower the pH of the skin, making it more difficult for certain odor-causing bacteria to multiple, says Dr. Engleman. The keyword here being "may." See, there isn't any scientific evidence to prove that GA really does play a role in squashing stench, according to board-certified dermatologist Hope Mitchell, M.D. (Related: Why You Should Add Lactic, Citric, and Other Acids to Your Skin-Care Regimen)
That being said, Dr. Mitchell has actually seen the effects of GA as a deodorant first hand. "I was skeptical until I recommended that my patients incorporate glycolic acids into their regimen, especially those who, in addition to body odor, had concerns of hyperpigmentation or ingrown hairs," shares Dr. Mitchell, who goes on to say that she's noticed an improvement in those patients who were worried about "mild to strong body odor or that 'musty' scent."
But what about other issues, such as sweating? Sure, some TikTok users might claim it's the secret to dry as the desert pits, but Dr. Engleman isn't as sold. "Glycolic acid has not been proven to reduce sweating, and as a water-soluble AHA, it has a limited capacity to even persist on wet or sweaty skin — meaning it does not make for an ideal deodorant," she says. "[But] because it speeds up cell turnover, glycolic acid can also reduce hyperpigmentation that sometimes appears in the underarms." If you're dealing with dark spots, though, Dr. Engelman recommends using other ingredients such as lactic acid or alpha arbutin, which are "gentler and more targeted solutions for hyperpigmentation." (Related: This Brightening Ingredient Is About to Be Everywhere — and for Good Reason)
At this point, there isn't any concrete evidence to suggest that swapping your go-to deodorant for a GA serum is a surefire way to stop sweat, stench, and other skin-related struggles. Given its potential ability to reduce B.O. and fade hyperpigmentation, however, it could be used sparingly (as in once or twice a week) to help keep underarms looking and smelling fresh. Sound up your alley? Then go ahead and try The Ordinary's Glycolic Acid 7% Toning Solution (Buy It, $9, sephora.com) — a mild exfoliating toner that's all the rage as an alternative deodorant on TikTok. Or you could add Drunk Elephant's Sweet Pitti Deodorant Cream (Buy It, $16, sephora.com) to your routine; this deliciously-smelling natural option is formulated with mandelic acid, another AHA that's said to be gentler than glycolic acid.