AHAs (alpha hydroxy acids) such as glycolic and lactic acid have long enjoyed the spotlight - and for good reason! These are your proven chemical exfoliants essential to most anti-aging, hyperpigmentation skin routines. Beyond these two, there are plenty of “new age” AHAs that get touted for similar skin benefits, and one of the newer kids on the block we want to shine a spotlight on is mandelic acid. As chemists, we always have to look at the available clinical evidence on these newer ingredients to see if they are actually worth the hype. In this comprehensive guide, we dive into what actual skin benefits mandelic acid can offer, how does mandelic acid compare to salicylic acid as well as the other AHAs, and which mandelic acid serums are worth trying. So let’s decode mandelic acid - chemist style!
What is Mandelic Acid
Mandelic acid is a compound that can be found naturally in bitter almonds, but as a skincare molecule, it functions as an alpha hydroxy acid (AHA). Mandelic acid is quite a bit larger in size than classic glycolic and lactic acid, making mandelic a much more gentle exfoliation experience.
Unlike glycolic and lactic acid, mandelic acid has a unique trait. It’s molecular structure is actually somewhat similar to BHA, salicylic acid. It’s because of this trait that mandelic acid products are often positioned for oily, congestion-prone individuals. In fact, there is a study that looked at the efficacy of 5% and 10% mandelic acid as a daily leave-on serum for individuals with acne. The study found that over the course of the 2 month testing period, subjects showed significant improvement in the number of pustules, the severity of inflammatory acne, and for subjects in the 10% group, even reported a reduction in sebum production! A very promising initial study for mandelic acid.
Mandelic Acid vs. Salicylic Acid: Which is Better for Acne?
With promising clinical evidence, we naturally have to ask the question - is mandelic acid secretly better than salicylic acid at treating acne? To address this question, we have to turn to a study done with chemical peels (read: we weren’t able to find any comparison studies for nightly use). One study evaluated a 45% mandelic acid peel compared to a 30% salicylic acid peel. The study participants received a peel every other week for 6 sessions. At the end of the study, both peel groups performed on par with each other in terms of reducing the total comedone count. Interestingly, the mandelic acid group performed better for inflammatory acne with less side effects.
In another chemical peel study, 10% mandelic acid was actually used in conjunction with 10% salicylic acid and compared to a 35% glycolic acid peel. While both groups were effective, the salicylic-mandelic acid combination performed better for active acne with less irritation.
So what’s our chemists’ takeaway? With only one study, there’s definitely not enough evidence to say that mandelic acid is the definitive, superior choice to salicylic acid. However, it can be a fantastic option for those with acne AND sensitive skin. For those less sensitive to acids, using the two in tandem could also be very beneficial This is part of the reason why we ourselves chose to formulate mandelic acid together with salicylic acid in our Specialist AHA BHA Treatment.
Mandelic Acid vs Glycolic acid for Hyperpigmentation and Anti-Aging
As you try to shop for mandelic acid, you might encounter products that position mandelic acid as an alternative to gold-standard glycolic acid. But can mandelic acid actually bring similar levels of efficacy as glycolic acid? Sadly, this is a comparison with not a lot of data to go off of so it’s difficult for us to give any firm answer here. In studies that evaluated mandelic acid for hyperpigmentation and anti-aging, the data does show that mandelic acid can bring efficacy for these skin concerns. However, from the available data, the degree of improvement doesn’t really warrant a direct comparison to glycolic acid. We would consider mandelic acid a fantastic supplement to an actives-packed routine to enhance overall efficacy, but would not say it’s a glycolic acid replacement.
Best Mandelic Acid Serum
All in all, we would say mandelic acid is a fantastic addition to your routine if you have oily, acneic, congestion-prone skin. If you have sensitive skin that seems to flare up easily with glycolic, lactic, or even salicylic acid, mandelic acid can be a fantastic alternative.
Best Mandelic Acid Serum for Beginners & Those with Sensitive Skin
For those with sensitive skin or the absolute AHA beginner, we recommend looking for a serum or toner between 5% to 10% for gentle yet effective daily use. Something like Paula’s Choice 6% Mandelic Acid toner or The Ordinary’s Mandelic Acid 10% is a great entry point to see if mandelic acid is right for your skin.
Chemists’ Pro-tip! Mandelic acid is not the easiest for us chemists to work with. So if you notice your lovely mandelic acid serum or toner slowly turn into a snow globe - it’s time to toss it! The crystals mean that it has not been properly stabilized in formula and will not give you the claimed skin benefits.
Best Mandelic Acid Serum for Stubborn Blackheads
As a larger, more gentle chemical exfoliant, punching up in concentration can bring a lot more benefits, especially for stubborn skin congestion such as blackheads. We have to give our very own Specialist AHA/BHA Treatment a shoutout here. It’s packed with 18% mandelic acid and 2% salicylic acid. At this level, it can be used as a leave-on spot treatment for zones with extra stubborn skin congestion and blackheads. For those of you who use a weekly home peel, the spot treatment is gentle enough that it doesn’t interfere with your home peel routine. Tackle that stubborn skin congestion with ease!
Chemists’ Pro-tip! You can use our Specialist Booster in multiple ways! Add a drop into your serum for daily upkeep to prevent stubborn congestion from taking root in the first place.
Mandelic Acid Skin Routine Tips & Key Takeaways
AHAs are an important part of any skincare routine because of their ability to regulate cell turnover. Remember! Regular, on schedule cell turnover is key to maintaining healthy skin function which is necessary for skin to function and look its best!
Of the new gen AHAs, mandelic acid can be a fantastic addition to your routine, especially if you have oily, acneic or sensitive skin. When shopping for mandelic acid, we find it’s easiest to shop based on your skin type. For those with sensitive skin types, a nightly treatment of at least 5% mandelic acid is an easy layer to reap those sweet sweet AHA benefits. For those looking to tackle skin congestion and blackheads, aim for higher concentrations of mandelic acid (higher than 10%).
Also don’t forget, good sunscreen habits are absolutely required with this arena!
References
Choińska, R., Dąbrowska, K., Świsłocka, R., Lewandowski, W., & Świergiel, A. H. (2021). Antimicrobial properties of mandelic acid, gallic acid and their derivatives. Mini reviews in medicinal chemistry, 21(17), 2544-2550.
Dębowska, R. M., Kaszuba, A., Michalak, I., Dzwigałowska, A., Cieścińska, C., Jakimiuk, E., ... & Kaszuba, A. (2015). Evaluation of the efficacy and tolerability of mandelic acid-containing cosmetic formulations for acne skin care. Dermatology Review/Przegląd Dermatologiczny, 102(4), 316-321.
Dayal, S., Kalra, K. D., & Sahu, P. (2020). Comparative study of efficacy and safety of 45% mandelic acid versus 30% salicylic acid peels in mild‐to‐moderate acne vulgaris. Journal of cosmetic dermatology, 19(2), 393-399.
Sarkar, R., Ghunawat, S., & Garg, V. K. (2019). Comparative study of 35% glycolic acid, 20% salicylic–10% mandelic acid, and phytic acid combination peels in the treatment of active acne and postacne pigmentation. Journal of cutaneous and aesthetic surgery, 12(3), 158-163.
Jacobs, S. W., & Culbertson, E. J. (2018). Effects of topical mandelic acid treatment on facial skin viscoelasticity. Facial Plastic Surgery, 34(06), 651-656.
