Maybe it happened on a sweltering summer day or after an especially intense session at SoulCycle, but if you’ve ever been afraid of being a little stinky, you know you’ll try practically anything to stop the stench. Lately, that could include using glycolic acid as a deodorant alternative, since the trend has been steadily going viral on TikTok. The hack—which involves skipping the stick deo and instead swiping on an acid toner—has plenty of people wondering if it’s safe to play cosmetic chemist at home and trade in your deodorant for glycolic acid.
Read on for everything you need to know about the glycolic acid deodorant hack taking over TikTok.
How Glycolic Acid Works as a Deodorant Alternative
Before we delve in, it’s important to understand the distinction between deodorant and antiperspirant. “I wish that everybody truly understood the difference between antiperspirant and deodorant,” says board-certified dermatologist Dr. Heather Woolery-Lloyd. “These terms are often used interchangeably but they really are quite different. Understanding these differences can really help people decide what’s the best product for their needs.”
So how do the two differ? “Deodorants use a ferment or probiotic to control bacteria growth to reduce odor, and they also use starch powders to absorb some of the moisture to help with the sweat,” explains Mary Futher, aka @Madame Sweat and founder of Kaia Naturals. “Antiperspirants stop sweat by using aluminum salts to block the sweat gland and prevent you from sweating, therefore no moisture is in the underarm causing bacteria, so you stay dry and do not smell.”
In other words, antiperspirant helps with sweat and odor, while deodorant only addresses odor. That puts glycolic acid in the same category as deodorant, though it works differently to fight funk. “Body odor is created with the interaction of sweat and normal skin bacteria,” says board-certified dermatologist Dr. Elyse Love. “Glycolic acid will not decrease sweating, but it does alter the skin’s pH, which potentially decreases the concentration of skin bacteria in the area. Less bacteria means less odor.”
The Risks of Using Glycolic Acid as Deodorant
You’ll want to proceed with caution when trying this trend, as is the case with any fad concerning the underarm. Remember that the lower the concentration of glycolic acid, the lower the risk of irritation.
“I would not consider this safe because the underarm skin is extremely sensitive,” Dr. Woolery-Lloyd says. “I would not recommend that anyone with sensitive skin or a history of eczema try this trend due to the significant risk of irritation and rashes. And in general, I would not recommend using glycolic acid in the underarms as a deodorant due to this risk of irritation in anyone. A simple trend like this can cause a severe rash and, for people with darker skin, hyperpigmentation could last months. In this case, the risks do not outweigh the benefits. This is especially true because there are so many safer affordable alternatives that can achieve the same goal.”
Futher concurs: “I must admit I am not a fan of this trend,” she says. “My opinion is that glycolic acid is not designed for underarms—it is designed to be used in facial products. The skin in the underarm region has a different pH, skin folds, friction from clothing and shave issues. Skin in the region also has a high temperature and is very warm, along with hair follicles. It is super complicated so for that reason I do not recommend DIY solutions for underarms.”
The Best Way to Use glycolic Acid as Deodorant
If you are going to try this trend, nailing application is essential, as it can cause trouble otherwise. Since glycolic acid comes in multiple formulas and concentrations, Dr. Love says it’s likely easier and more convenient to seek out a product specifically formulated for the underarms (like the Kosas Chemistry AHA Serum Deodorant, $16).
“Glycolic acid can be irritating if used incorrectly at too high of a concentration or too often,” cautions Dr. Love. “A low percentage glycolic acid toner is potentially the best way to try this trend. A thin layer can be applied to dry underarms once daily. It’s important to allow the underarms to dry completely before lowering them. It is safe when used correctly but too high concentrations of glycolic acid, too much glycolic acid, or too frequent use can possibly lead to irritation, burns and pigmentation.”
A Safer Swap for Glycolic Acid as Deodorant
There’s no need to DIY when deodorants and antiperspirants have the latest technology. “Antiperspirants are becoming more advanced. For example, Degree now has motion-activated microtechnology, in their Advanced Protection Antiperspirant collection, that slowly releases fragrance and freshness with movement to provide odor and sweat protection for 72 hours without reapplication,” says Dr. Love, who works with the brand.
Glycolic acid isn’t the only underarm ingredient that’s trending. “Salicylic acid is an ingredient that is commonly used as a treatment for ingrown hairs,” Dr. Woolery-Lloyd says. “The products that contain salicylic acid are most used in the bikini area and less frequently used in the underarms. They work by exfoliating the skin to help release trapped ingrown hairs.”
Those who have hyperpigmentation in the underarm can look for a formula with niacinamide, which brightens skin. “I just launched Kaia Naturals Takesumi Bright ($26), a niacinamide deodorant with alpha arbutin (which is tested and designed for those who want a brightening effect) and niacinamide and aloe, which are skin-friendly for underarms,” Futher says. “It was designed for sensitive underarms as well as those that suffer from post inflammatory pigmentation.”
Ultimately, Dr. Woolery-Lloyd says it’s better to choose a deodorant that has been formulated specifically for the sensitive underarm area. “If someone is looking for alternative ingredients, they should look for a product with 0% aluminum, such as Dove 0% Aluminum Deodorant Spray ($9), because it offers instant odor control with no harsh ingredients,” she says. “As a dermatologist, I also like that it contains moisturizers, which Dove also has, so it’s safe for the sensitive skin on the underarms.”
When it comes down to it, playing it safe when it comes to your pits will give you one less thing to sweat over.