Thanks to our own professional curiosity, we broached this topic with a few experts, and it turns out that what could be considered a small detail isn't so small at all. It's almost like comparing a plain pizza with a supreme pie — sure, they're both delicious, but the taste couldn't be more different.
But first, why should you care? Well, it's important to understand the differences, benefits, and drawbacks of what these different acids are doing alone and together, no matter if you're interested in at-home, spa, or derm peels. So use the below info as your guide to determine what kind of acid peel is better for you.
So What's The Difference, Anyway?
This is partially common sense, of course. "A single-acid peel, like a glycolic peel for example, uses just one type of acid, typically to achieve skin-resurfacing," celeb dermatologist Harold Lancer, MD, tells us. Meanwhile, "A multi-acid peel, like a Jessner's peel, combines various types and strengths of acids to more deeply rejuvenate the skin, [and] remove sun damage or excessive pigmentation." [Ed. note: A Jessner peel is the common name for a certain mix of acids, but more on that later.] So basically, the more acids, the better, right? Not always.
A single-acid peel, like a glycolic peel for example, uses just one type of acid, typically to achieve skin-resurfacing.
Selecting a single-acid peel can allow you to effectively target the area of concern, with less downtime or risk of irritation or allergic reaction. (Translation: The more ingredients on your pizza, the more chances one of them will disrupt your stomach or displease your palate.)
The most popular acids are naturally derived. "There are many types of refined fruit-enzyme [acids] that are gaining popularity among dermatologists and aestheticians for their gentle effects, which can imitate the effects of a deeper peel when repeated over a period of time," Dr. Lancer says.
When asked what the most commonly used acids do, Dr. Lancer broke it down like this: Salicylic acid helps dissolve built-up sebum (bye-bye, oil!). Glycolic is great for brightening and smoothing rough, ruddy, or uneven skin (see ya, unevenness!). And lactic acid is great for acne, fine lines, and brown spots — and is the most gentle of the alpha-hydroxy acids (toodles, irritation!).
There are many types of refined fruit-enzyme [acids] that are gaining popularity among dermatologists and aestheticians for their gentle effects.
For proof that single acids don't come second to blends, look to the final two commonly used by Dr. Lancer. There's TCA, or trichloroacetic acid, which is a more intense acid that "can help reverse sun damage and signs of aging, but requires more recovery time," he says, and carbolic acid, an extremely powerful acid that you often have to be sedated for, used to "reverse significant, precancerous sun damage."
Now that you understand a bit about what single acids do, we'll talk about what can happen when they're combined. By blending different acids, a professional can create cocktails that work on different issues simultaneously. However, some acids, when combined, negatively affect each other — so don't think you can start mixing them at home without knowing what you're doing. "It's really sketchy for anyone that's not quality-controlling the batch to put acids together," Benjamin explains. "When you mix two or more acids together, the pH should be adjusted to a safe [level]."
[Mandelic acid] is a great first-time chemical peel because it's less penetrating and irritating, but still very effective for treating damaged skin.
Which is one reason, as Dr. Lancer mentioned above, there are certain blends of acids that are widely used — and even have nicknames, like Jessner's peel. This popular cocktail is a multi-acid concoction "formulated with salicylic acid, which assists in penetration, lactic acid for exfoliation, and resorcinol, which assists the action of the lactic acid," says Dr. Lancer. "This peel can do wonders for someone dealing with the significant signs of aging, dry, dull skin, brown spots, fine lines, and crepe-y skin, but is less effective for treating, say, melasma or general dullness."
Benjamin agrees with this sentiment. "I always recommend doing a consultation with your skin therapist to understand the benefits and any potential side effects to determine the best peel for you," she says.
Which brings us to the conclusion: The more you know, the more prepared you'll be to understand what you're getting, no matter if it's a home peel, spa treatment, or derm procedure. It may not be as easy as pie — but hardly anything is.