Here's Everything You Need to Know About Glycolic Acid
Do a quick scan of ingredient labels on your skin-care stash and we're willing to bet you'll find at least one product that contains glycolic acid. It's by no means the newest kid on the block-it's been used in skin care for decades. But it certainly is one of the most popular and effective. Like other acids, glycolic acid is top-notch exfoliator, dissolving dead skin cells to leave your complexion smooth and glowy, though the benefits don't stop there. Ahead, the lowdown on this A+ acid.
What's Glycolic Acid?
Glycolic acid (GA) is an alpha hydroxy acid derived from sugarcane. Not only is it one of the most commonly used AHAs, it's also the structurally simplest of the bunch, as well as the smallest. "It's small size means it can easily penetrate the skin, which is what makes it so effective," says Kenneth Howe, M.D., a dermatologist at New York City's Wexler Dermatology. Couple that efficacy with the fact that it's fairly gentle and delivers multiple different benefits (more on those to come), and you've got yourself a winning ingredient that can be incorporated into all kinds of products. (Related: Why You Should Add Lactic, Citric, and Other Acids to Your Skin-Care Regimen)
How Does Glycolic Acid Work?
Put simply, GA is an exfoliant. It loosens the bonds between corneocytes-dead skin cells-stuck together on the stratum corneum-the outermost layer of the skin. As these dead cells build up, they thicken the stratum corneum, resulting in rough, uneven, and dull skin, explains Dr. Howe, which is exactly why glycolic acid is a choice ingredient for anyone who wants a more even, radiant complexion. (See: 5 Skin-Care Ingredients That Get Rid of Dull Skin and Help You Glow From Within)
Also worth noting: "Glycolic acid also acts as a humectant, attracting to and holding moisture in the skin," notes Sejal Shah, M.D., founder of SmarterSkin Dermatology. This makes it a great option for anyone with dry skin, for whom other methods of exfoliation might be too harsh or drying, she adds. Still, what sets glycolic acid apart from all the (many) other acids and other exfoliants out there are its abilities to do more than just exfoliate. Not only does it work on the surface of the skin, it also penetrates into the deeper layers and can help stimulate collagen production over time, while also having anti-inflammatory and antioxidant effects on the skin, says Dr. Howe. Translation: It's an excellent anti-aging ingredient. Multitasking for the win. (Related: Why It's Never Too Early to Start Protecting the Collagen In Your Skin)
Who Should Use Glycolic Acid?
Pretty much anyone and everyone, since it's overall fairly well-tolerated in most people. Still, if your skin skews towards sensitive or you have eczema or rosacea, take note. "Glycolic acid, however mild, is still an acid and can irritate your skin, especially if it's more prone to irritation to begin with," cautions Dr. Howe. (More on what you should look for and what products to use in a minute.) Unlike many other top skin-care ingredients (we're talking about you, retinol) glycolic acid is also safe to use during pregnancy, though Dr. Shah does suggest using it in concentrations less than 10 percent while pregnant.
How to Pick a Glycolic Acid Product
Fun fact: Googling "glycolic acid skin-care product" yields almost 7 million results. Clearly, there's no shortage of skin care touting the ingredient, and with everything from glycolic acid washes to toners to creams to peels out there, it can be tricky to find the best one for you. If your skin is sensitive, a GA cleanser is your best bet, since the time the ingredient is in contact with your skin before it's washed off is minimal. We're big fans of the Glytone Mild Cream Cleanser ($33; dermstore.com). (You can even play it extra safe and start by using it only a few times a week, and gradually increasing the frequency as your skin acclimates.)
Serums, like the BeautyRx by Dr. Schultz Essential 8% Exfoliating Serum ($65; beautyrx.com), and daily peel pads, like Bliss That's Incredi-Peel Spa Strength Glycolic Resurfacing Pads ($20; target.com) are an easy way to reap the exfoliation and anti-aging benefits. (Though it's important to keep in mind that how you use the pads can change the intensity of the glycolic acid. The more times you wipe it across your skin, the greater the effect, notes Dr. Howe. Bottom line: Follow the product directions.)
And if you're treating the skin on your body-GA is a great ingredient for conditions such as keratosis pilaris (KP), those bumps on the back of your arms-Howe recommends lotion. "They're easy to apply on large areas, and a longer contact time is necessary for it to work on these types of conditions." Try: SLMD Glycolic Acid Body Lotion ($38; slmdskincare.com).
Important Tips for Using Glycolic Acid
How often you use glycolic acid largely depends on the type of product you're using. Cleansers/lotions/pads/serums/toners are usually best used once a day, while peels and masks can be used a few times per week. "Because glycolic acid is an exfoliant, it does have the potential to make your skin more sensitive to the sun, so save it for nighttime," adds Dr. Shah. (Related: 10 P.M. Skincare Products That Work While You Sleep)
There's also a difference between buffered and unbuffered glycolic acid: "Buffering an acid alters its pH to make it less acidic, so unbuffered glycolic acid is going to be much harsher and stronger on the skin," explains Dr. Shah. Stick with buffered to minimize irritation; most OTC products are buffered to begin with, as unbuffered glycolic acid is typically reserved for in-office peels. If you ever do feel like you OD'ed on GA, remember that water neutralizes it: "If your skin starts to burn or sting, just rinse the product off thoroughly and the glycolic acid will be inactivated," points out Dr. Howe.