This Powerful Exfoliating Ingredient Brightens Skin and Fights Aging

Have complexion concerns? Glycolic acid to the rescue. It’s an extraordinary exfoliator that can help address a multitude of skincare issues, from spots to dullness to wrinkles. While it’s not the newest kid on the block, it remains a staple in all kinds of different skin-care products, no matter how many trendy new ingredients may come and go. There’s a good reason why. Yes, it works as many other acids do—dissolving dead, dry cells that sit on the surface of the skin and leave your complexion looking dull and lackluster. But it goes above and beyond the standard call of duty, delivering a host of other benefits as well. Here’s what you need to know before you add it to your beauty regimen.

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What Is Glycolic Acid?

Glycolic acid belongs to a group of acids known as alpha-hydroxy acids (often referred to as AHAs) and is derived from sugarcane. So, what sets it apart from other AHAs commonly used in skincare? “Glycolic acid has a smaller molecular size than the others, which allows it to better penetrate the top layers of the skin,” explains dermatologist Tara Rao, M.D., of Schweiger Dermatology Group in New York City. Improved penetration means it can work more effectively. Couple that with the additional skincare benefits it offers (more on those in a minute) and it’s no surprise that glycolic acid is one of the most popular AHAs—and skincare ingredients in general—out there.

Related: How to Restore Your Skin's Balance

What Can Glycolic Acid Do for Skin?

First and foremost, glycolic acid is a great chemical exfoliant. “By dissolving the dead cells on the outermost layer of the skin, the stratum corneum, it leaves skin smoother and brighter,” says Chicago dermatologist Jordan Carqueville, M.D. More even, more radiant skin? Yes, please. But the exfoliating benefits don’t stop there. “This also enhances the penetration of other topical ingredients that you might be using, such as vitamin C or retinoids, and makes them even more effective. Plus, glycolic acid can also help keep your pores clear, making it a great option if you’re acne-prone,” adds Dr. Carqueville.

Besides the excellent exfoliation, it also acts as a humectant—AKA a hydrating ingredient that works by attracting water to the skin. And that makes glycolic acid ideal for anyone who finds other acids to be too drying.

But here’s what really sets it apart from other acids. Besides acting on the surface of the skin, glycolic acid can also penetrate into the deeper layers, where it can help stimulate collagen production over time. As a reminder, collagen is the protein responsible for firm, healthy, youthful skin. More collagen equals fewer wrinkles, which is why glycolic acid is such a great ingredient to incorporate into any anti-aging routine.

Related: 8 Anti-Aging Hacks That Will (Almost) Turn Back Time

Who Can Use Glycolic Acid?

Relatively speaking, glycolic acid is generally well-tolerated by most people. That being said, it is an acid and exfoliant, and so it can cause irritation and dryness, cautions Dr. Tao. She recommends avoiding it if your skin is irritated and inflamed to begin with (i.e. if you’re dealing with a condition such as rosacea or eczema). And while glycolic acid does have some hydrating properties, it’s still a good idea to still make sure you’re using a plain moisturizer with it, particularly if your skin is on the sensitive side, suggests Dr. Carqueville.

What Are the Best Glycolic Acid Products to Use?

To say your choices are endless would be an understatement, given that you can find pretty much any type of product—from cleanser to cream to mask to peel—that contains the ingredient. And the vehicle it comes in does matter, according to Dr. Carqueville. Those with sensitive skin should consider starting with a cleanser since the amount of contact time with your skin is minimal. We like Glytone Mild Gel Cleanser, $33, available at Dermstore. Leave-on products—think serums and daily peel pads—are a great way to easily and effectively reap both the anti-aging and exfoliating benefits. Try the First Aid Beauty Facial Radiance Pads, $32, from Sephora, which blends glycolic with another AHA, lactic acid, and can be used daily on both your face and chest.

Some products will also specify the percent of glycolic acid they contain; at-home products generally have between eight and 30%, compared to in-office peels which may contain up to 70%, notes Dr. Carqueville. The percentage will play a role in both its efficacy and the potential for any irritating side effects, she adds, so if your skin falls on the sensitive side, stick with lower percentages (less than 10%).

Still, as with lots of skincare, you may just need to experiment and rely on some good old fashioned trial and error: “Ultimately, your best bet may be to try out a few different products and see what works best for you,” advises Dr. Tao. It’s worth noting however that, like other acids, glycolic acid can make your skin more susceptible to the sun. No matter what type of product you end up with, reserve it for bedtime use and don’t forget to be extra diligent about applying SPF during the day.