According to dermatologists, using at-home products with concentrations of 10% or less will help reduce inflammation. Basically, you want to clear your pores (more on that below) without stripping your skin to the point where it’s raw and inflamed.
Less zits and more clear pores.
Because it’s so effective at sloughing off the top layer of skin, glycolic acid can also be beneficial for banishing blemishes. “Chemical exfoliation can help people with acne by clearing dead skin cells and pore-clogging debris,” Dr. Marcus says.5
For anyone who’s both breakout-prone and super sensitive, though, glycolic acid may be too harsh, she notes. She suggests giving your skin breaks in between treatments and applying exfoliants only two to three times a weeks.
But if your face still isn’t happy, salicylic acid might be a better exfoliating acne treatment for you, Dr. Marcus says. As we mentioned above, it can penetrate deeper into pores to unclog them, and it’s also been shown to be less irritating than glycolic acid.1
There are fewer dark spots due to sun damage.
The sun’s UV rays can cause hyperpigmentation (or dark spots). The glycolic acids help to remove dead skin cells and can remove excess pigments (or melanin), says Loretta Ciraldo MD. She is a board certified dermatologist, volunteer assistant professor at the University of Miami Miller School of Medicine.3
It can also have the opposite result in some cases. Especially if you’re prone to hyperpigmentation (a common issue for people with medium to dark brown skin tones, for example, as the body already makes extra melanin, which can lead to dark spots), glycolic acid could make the issue worse. It has been found that high concentrations of glycolic acid can cause inflammation. This could then lead to hyperpigmentation.6 2
You don’t necessarily have to skip glycolic acid just because you tend to get dark spots, but to be safe and minimize irritation, you should stick with low concentrations (think 5 to 10%), according to Dr. Ciraldo. Dr. Marcus also says that applying it one or two days a week is enough to calm skin.
Thicker, plumper-looking skin.
While glycolic acid is busy removing the old skin, it promotes new cells. As a result, “it can thicken the skin, stimulate collagen production, and improve tone and texture,” Dr. King explains.3 “Studies have shown, for example, that using a topical glycolic acid cream for six months stimulated a 27% increase in epidermal thickness.”7
In essence, as glycolic acids remove the dead cell layer, they are replaced with new, healthy cells. The thicker and more collagen-rich skin will give you the plumpness and smoothness of a newly-done face.3
What ingredients can I safely combine with glycolic?
Dr. King says that you shouldn’t mix glycolic acid and other AHAs or BHAS like salicylic acids, as they may be too strong together and cause irritation. One exception is fellow AHA lactic acid, since it’s pretty gentle: The two chemical exfoliants can work well together to smooth fine lines and cut back on surface-level dark spots, and you may even find them in the same products, she says.8 “The result of combining the two is smoother and softer skin that’s moisturized and has fewer discolorations,” according to Dr. King.9