Mandelic acid: what is it and how can I use it? Mandelic acid is an exfoliating alpha hydroxy acid (AHA). But to understand it, we first need to know: where does mandelic acid come from? Well, it can be derived from bitter almonds or synthetically created. For decades, it has lived in the shadows of the more popular AHAs, like lactic or glycolic acid, but we think it's mandelic acid's time to shine! Mandelic acid is the more soft-spoken member of the AHA family. It is gentle, more subdued and so often overlooked. But it still maintains the same benefits usually associated with other AHAs: evening out tone, tackling sun damage, smoothing texture and helping decrease the look of fine lines & wrinkles. The original version of this article was reviewed by Dr. Debra Jaliman, MD, USA How mandelic acid works: This gentle ingredient aids the skin primarily through exfoliation. Like other AHAs, it works to loosen the bonds between skin cells – which allows dead & dull cells to shed away. In this process, mandelic acid reveals healthy and radiant skin. Mandelic acid differs from other AHAs due to its molecule size. Imagine it as a basketball, whereas lactic acid is a baseball and glycolic acid is a tennis ball. This larger molecule size allows mandelic acid to penetrate the skin in a slower manner, which makes it gentler. AHAs are water-soluble, meaning they can’t sink too far into the skin. However, mandelic acid can accomplish gentle yet multi-level benefits by slipping beneath the skin’s surface, where it morphs and becomes oil-soluble. Mandelic acid benefits Speaking of multi-level benefits – mandelic acid not only exfoliates the skin, it also... Helps smooth texture by increasing cell turnover rate Visibly reduces the appearance of fine lines & wrinkles Fades multiple signs of sun damage for a more even complexion Supports skin’s architecture, promoting firmness & elasticity (according to a 2018 study that included application to the under-eye) Assists in reducing clogged pores and the occurrence of breakouts (most research covering this benefit uses mandelic in conjunction with other acids, so if you’re seeking this benefit, alternate between both AHA & BHA exfoliants) Targets & reduces the look of dark spots by getting in the way of an enzyme that contributes to their creation (research even shows it’s particularly suited for assisting deeper skin tones with this concern, ie. those with a 4-6 Fitzpatrick skin type) Is mandelic acid good for dry skin or oily skin? Mandelic acid works well for all skin types, though it is a particularly good option for sensitive skin due to its gentle nature. It might also be your choice of chemical exfoliant if you have drier skin, as some studies have shown that in higher concentrations, mandelic acid can promote healthier sebum production. Just a quick assurance to those looking to use mandelic acid with oily skin: mandelic acid leave-on exfoliants aren’t known to trigger oil. Dermatologist Dr. Debra Jaliman recommends “adding mandelic acid to your skincare regimen especially if you have sensitive skin and want to smooth and even your skin tone while also seeking to diminish the look of brown spots." Which is better: mandelic acid or lactic acid? Though both exfoliating AHAs, they differ in their benefits. You'll likely have heard of lactic acid as a popular exfoliating ingredient. Good to know that it has a smaller molecule size compared to mandelic acid and is extracted from milk (though most skincare formulas use synthetically made, due to its stability & vegan designation). So what is mandelic acid used for in contrast to lactic acid? Mandelic acid: Gentle Suited to sensitive skin Particularly adept at tackling uneven skin tones Lactic acid: Best for sun-damaged dry skin Adept at boosting hydration & supporting the skin barrier We don't feel the need to pick a favourite because mandelic acid & lactic acid complement one another so well! Especially when our 6% Mandelic Acid + 2% Lactic Acid AHA is the true next level of exfoliation, carrying the benefits of each AHA. Can mandelic acid be used with azelaic acid? Azelaic acid and mandelic acid share a gentle nature and a penchant for promoting even skin tones, so combining them in a single routine is a no-brainer for sensitive skin prone to dark spots or redness. This combination is even suitable for those prone to rosacea. Mandelic acid for skin has a long history as a supporting ingredient, meaning it’s often paired with other acids and bio-active ingredients in peels and products. Combining these two acids is safe and easy. Apply your choice of mandelic acid exfoliant and follow with an azelaic acid serum or treatment. Read on for your mandelic acid skincare routine in full! Can mandelic acid be used with retinol? Let us quickly pop our myth-busting heads on: you can use mandelic acid and retinol in the same routine. Remember how we said mandelic acid has a long history of use in formulas with other bio-active skincare ingredients? Well, this isn't limited to exfoliating acids. In a 2019 study focused on acne-prone skin, mandelic acid was safely paired with retinol, benzoyl peroxide, retinyl palmitate and glycyrrhetic acid. Although mandelic acid's pairing with retinol often happens in clinical settings, you can use them together in the comfort of your own home. Ease into your use of both mandelic acid and retinol. Begin by switching between the two, using them both once or twice a week on separate occasions. In time, after noting your skin's response, you can reach the point of using both actives in the same evening routine. Not all skin needs this level of treatment; it's most suited to acne-prone skin with signs of ageing as you can also visibly improve post-breakout marks. How often should you use mandelic acid on your face? We often hear: can I use mandelic acid every day? We always answer with yes, once or even twice a day. But it's important to note that if you’re newer to exfoliants or have sensitive skin, start with just once or twice a week and see how your skin responds. This way, you can gradually work up to your preferred cadence. After cleansing and toning, apply your mandelic acid exfoliant with your fingers or a cotton pad. No need to rinse. Leaving exfoliants on the skin gives them time to carry out their work. Always follow with SPF during the day and moisturiser at night. If you’re an exfoliant pro looking to chip away at more stubborn skin concerns, you might find that you want to alternate use of a mandelic acid exfoliant with other exfoliants, like BHA. You can even layer them if your skin permits. Our trial kit includes the iconic BHA + the breakthrough AHA, two formulas that will work both above & below your skin's surface so you can see multi-level exfoliation results. Keep in mind: exfoliation is an individualised balancing act that's all about making sure you don't tip the scale. Take it slow: the potential for irritation outweighs any benefits. What are the best mandelic acid products? The best mandelic acid formulas are those bolstered by a cast of supporting acids and replenishing ingredients. It’s also important to note that the most effective mandelic acid products are packaged in airtight, opaque containers and formulated within the 3-4 pH range. The mandelic acid in your exfoliant can be plant-derived (from bitter almonds) or synthetically created. Both forms are equally effective, though the almond-derived type may prove problematic for those with nut allergies. AHAs work particularly well when paired with one another, handing off what they can’t individually accomplish to their AHA family members. They also work wonderfully when included in the same formula as antioxidants, skin-soothers and hydrators. 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