Chemical peels. They’re great for improving acne, reducing lines and wrinkles, smoothing out texture, and giving skin a really good exfoliation - like, really good. The chemical peel benefits are almost endless. But, what makes a chemical peel, you know, chemical? Let’s demystify 10 of the most common acids used in chemical peels.
3 different types of chemical peel
The ingredients that make up the different chemical solutions in these peels are acids. Yes, I know. Actual acids. But, they’re not really that scary (especially if you choose a well-trained practitioner like the ones you'll be able to book with on Glowday!).
And if you’re thinking “What’s a chemical peel?”, go and give this article a read first!
Which acids are used in superficial chemical peels?
Superficial chemical peels (also called light chemical peels) use acids which remove the outer epidermal layer of skin. Basically, they exfoliate the very top layer of skin off. The majority of these acids are AHAs and BHAs, but there are some exceptions.
Ahh yes, the cult skincare product that you’ve probably seen everywhere. And it’s famous for good reason. This sugar cane-derived AHA is liquid gold and can help almost all skin issues - though it’s most suited to dry and mature skin types. With the smallest molecular size of all the AHAs, it’s really good at penetrating the skin for effective exfoliation which smooths and brightens. Glycolic acid is very versatile and can treat signs of ageing (like superficial wrinkles), discolouration and bumpy skin texture - it also helps keep the skin clear of breakouts. No wonder it’s one of the most popular acids for chemical peels!
Another AHA, lactic acid is extracted from lactose. Yep, the stuff found in milk also has benefits for the skin. This AHA is gentler than glycolic acid, so it’s a good choice if you have sensitive skin, but still want powerful exfoliation. But, even though it’s milder than glycolic acid, this type of chemical skin peel still effectively targets signs of ageing, pigmentation and acne. Two of the most notable things about lactic acid are its ability to lighten the skin (perfect for hyperpigmentation and dark spots) and its hydrating effect. It strengthens the skin’s lipid barrier, helping to prevent water loss - so it’s great for giving dry, dehydrated skin some TLC.
This willow bark derivative is a dab hand at tackling oily and acne-prone skin (especially comedonal acne). A BHA, this acid has lipophilic and comedolytic properties... Everyday terms, please? Basically, it’s attracted to oil (perfect for oily skin) and has anti-pore-clogging power. It gets deep into pores, gives them a thorough clean and dissolves blackheads. Oh, and it’s also anti-inflammatory. Could it get any better? I think not. The breakout-banishing abilities of salicylic acid are so good, in fact, that one study found comedones were reduced by 53.4% with this type of peel. This is compared to Jessner’s solution (another acne-attacking peel that I’ll come to later), which cleared up comedonal acne by 26.3% - so, salicylic acid is pretty great stuff.
If your skin is at the sensitive end of the spectrum, you’re in luck. Mandelic acid (derived from bitter almonds) has the largest molecules of all the AHAs, meaning it penetrates the skin slowly, without causing irritation. It can help improve your typical skin gripes like fine lines and sun damage, but what’s the biggest turn-on with this acid? It’s a class-A acne fighter for mild to moderate breakouts, thanks to its antibacterial nature - wooo!
Looking to help lift areas of discolouration, pigmentation and age spots? Well, here you go. Phytic acid (found in rice, nuts and seeds) has skin-lightening properties, working by inhibiting the formation of melanin. What’s melanin? It’s the pigment in our bodies that’s responsible for our skin, hair and eye colour. This is also a pretty gentle acid, so it’s good for sensitive skin that needs a little bit of brightening, without being too harsh on the skin.
Retinoic acid is a type of retinoid, meaning it’s a derivative of vitamin A - one of the most celebrated vitamins for skin health. Sounds good so far! This acid has small molecules, so it can travel deep into the skin, fighting away signs of ageing (like lines and wrinkles) as it goes. And, since this acid boosts collagen production, it leaves the skin looking youthful and plump. It also gets an A+ for getting rid of acne, helping to unclog pores and keep breakouts away.
Which acids are used in medium-depth chemical peels?
Okay, moving on to medium-depth chemical peels. These peels exfoliate away a little bit more skin than superficial peels, removing the outer epidermal layer and the top dermal layers of skin.
This one’s a bit of a mouthful, so I’ll shorten it to its more manageable initials, TCA. Yielding dramatic results - you only have to do a Google image search to see - TCA is a very popular (and strong) medium chemical peel acid that’s particularly good for tightening the skin by stimulating collagen and elastin production. It’s also effective for acne scarring, pigmentation and fine lines and wrinkles. In higher or lower concentrations, this acid can also be used in light and deep chemical peels - so it can deal with all your skin needs!
Worried one acid isn’t enough for your chemical peel? How about three? Jessner’s solution typically combines three ingredients: lactic acid, salicylic acid and resorcinol. This chemical peel treatment is another favourite for oily and breakout-prone skin because it’s bactericidal (bacteria-killing), meaning acne doesn’t stand a chance. But, the benefits of Jessner’s solution don’t stop there. It also effectively evens out skin tone (goodbye age spots, discolouration and hyperpigmentation), reduces fine lines and wrinkles and improves scars. It’s not the best choice for dry skin, though, because it can be a bit drying.
This might be a lesser-known acid, but it’s a powerful one, nonetheless. Stronger than glycolic acid, but less potent than TCA, pyruvic acid is a great chemical peel for acne (even cystic acne), hyperpigmentation, photodamage and light scarring (the list goes on!). This acid also encourages collagen production which firms, plumps and tightens skin - who doesn’t want a collagen boost?
Which acids are used in deep chemical peels?
Deep chemical peels go deep. This might seem like a silly thing to say (or type!), but deep chemical peels really are invasive treatments which go down as far as the reticular dermis. So, they’re to be strictly administered by professionals only! In this section, we’re going to look at a skin sloughing giant in the chemical peel world: phenol.
Otherwise known as carbolic acid, phenol (when used alone) is the most powerful peeling agent of all - and you’ll soon see that it’s a force to be reckoned with! This chemical will sort out severe skin issues which other peels just can’t hack - like deep lines and wrinkles, pitted acne scars, sun damage and persistent pigmentation issues. Results can be dramatic and long-lasting - as in years long. Sounds good, right? The procedure does come at the price of pain, though. This deep peel even requires general anaesthetic or sedation - yikes! The chemical peel side effects are also considerably more extreme with phenol and the skin can take 2-3 weeks to heal, with redness lasting for months.
So, there we have it! The most common chemicals used in chemical peels all compiled into one handy article. Hopefully this will have cleared up your questions about the different types of chemical peels out there and which ones might be best for your skin type.