Mandelic Acid: Why It's A+ For Sensitive Skin, How To Use It & Best Products
How familiar are you with your exfoliating ABCs? Some players definitely receive more fanfare than others (glycolic acid, lactic acid, and salicylic acid are widely known crowd-pleasers), but we suggest another ingredient that deserves a space on your shelf, especially if you have sensitive skin: mandelic acid.
This lesser-known acid buffs your skin smooth without ravaging your complexion raw—below, derms explain everything you need to know.
What is mandelic acid?
Mandelic acid is a member of the AHA family, which means its main gig is to exfoliate, brighten, and stimulate cell turnover. Like other AHAs, it's derived from plants—in mandelic's case, bitter almonds—and it hydrates the skin while sloughing off dead cells. As board-certified dermatologist Mona Gohara, M.D., tells us about the acid family: "They can be simultaneously exfoliating and hydrating, making them very beneficial to many skin types."
Some AHAs can be more intense than others—glycolic acid, for example, has the smallest molecular weight of the bunch, which means it can penetrate the skin's outer layer quite easily. Mandelic acid, on the other hand, is larger in molecular size (even larger than lactic acid!), which may make it more tolerable for easily irritated skin types.
"It's my absolute favorite AHA—way underrated in my opinion—as it is the most gentle," says board-certified dermatologist Roberta Del Campo, M.D. "Meaning, anyone can use it, but it is just as effective as other AHAs, such as lactic acid and glycolic acid."
What does it do for skin?
As mentioned above, mandelic acid is an exfoliant: It buffs the skin bright and smooth, fades hyperpigmentation, and can reverse signs of skin aging. But let's break down those benefits even further:
Helps shed dead skin.
"AHAs exfoliate skin by breaking the connection between dead skin cells in the top dead skin cell layer, called the stratum corneum," says board-certified dermatologist Cynthia Bailey, M.D., founder of Dr. Bailey Skin Care. Sloughing off dead skin cells can prevent buildup (which commonly leads to gripes like dullness and clogged pores) and provide you with a lit-from-within glow.
Stimulates cell turnover.
"Exfoliation can improve skin circulation, encourage skin turnover, and improve the absorption of certain skin care products," board-certified dermatologist Raechele Cochran Gathers, M.D., once told mbg. This benefit can also help soften the appearance of fine lines: One 2013 study found that chemical peels containing mandelic acid were able to help stimulate collagen production and reduce signs of aging1.
Fades dark spots.
By promoting cell turnover, you can help push fresh, baby skin cells up to the surface—which can lessen the appearance of dark spots. In fact, a skin care regimen containing mandelic acid and vitamin C was associated with a 73% improvement in the appearance of post-inflammatory hyperpigmentation and melasma1.
"Mandelic acid has a unique affinity for oil compared to other AHAs," says Bailey. "It can penetrate deeper into oily pores and has even been shown to reduce [excess] sebum production and oily shine2." Typically, BHAs (like salicylic acid) are beloved for their ability to break through oil and unclog pores, which makes mandelic acid an interesting player in the space, for sure.
How to use mandelic acid.
It depends on your product of choice (check out our recommendations below), but you'll generally want to use mandelic acid during your nighttime routine since many acids can increase photosensitivity (and on that note, always make sure you're applying sunscreen daily).
For some general instructions: If you have a mandelic-infused cleanser, you'll want to follow with soothing ingredients post-wash; avoid any AHAs, BHAs, or retinoids for the rest of the night. And if you have a potent serum, apply it after cleansing and pre-moisturizer as your treatment step.
As for masks and peels, these are typically tossed into a routine whenever you want an extra shot of benefits: Apply the formula on clean skin right after your wash, let it sit for a few minutes according to the packaging's instructions, then wash off and continue with gentle ingredients.
How long does it take to work?
Of course, it depends on your individual skin type and the products you're using—hyperpigmentation, for example, is notoriously difficult to get rid of, as it can take months to completely clear. If your main goal is to simply resurface the skin and promote cell turnover, you may see quicker results. In terms of mandelic acid's oil-balancing properties, one study showed that it may begin working in as little as one week, with visible changes by eight weeks2.
What are the side effects?
"Minor redness or dryness may occur, but the beauty of this ingredient is it tends to be very gentle," says Del Campo. Even though the acid does have a larger molecular weight, it still has the potential to trigger flares, especially if you've exfoliated your skin too much.
Bailey agrees: "Side effects with mandelic acid are similar to other AHAs, in that the acidic pH can irritate sensitive skin," she says. That said, just make sure to notice when your skin has had enough: Typically, the signs manifest as irritation, redness, inflammation, and sometimes even breakouts.
What types of products contain mandelic acid?
You can find mandelic acid in a smattering of exfoliating cleansers, serums, creams, and masks—these are our favorites on the market.
If you're looking for a gentler acid fit for sensitive skin, may we suggest this underrated option? Mandelic acid has a larger molecular weight, which makes it penetrate slower and cause less irritation—yet it has some unique benefits that make it one supercharged ingredient.
Jamie Schneider is the Beauty & Wellness Editor at mindbodygreen. She has a B.A. in Organizational Studies and English from the University of Michigan, and her work has appeared in Coveteur, The Chill Times, and Wyld Skincare. In her role at mbg, she reports on everything from the top beauty industry trends, to the gut-skin connection and the microbiome, to the latest expert makeup hacks. She currently lives in New York City.