What Are AHAs?

Here’s what you need to know about these exfoliating acids and whether they are right for you.

what is aha

Alpha Hydroxy Acids, or AHAs, are not a new ingredient in skincare and it’s fair to say that these chemical exfoliators have become staples in many of our beauty routines. But as the popularity of AHAs has grown, so have instances of over-exfoliation, leading to a compromised skin barrier, redness, and irritation. While AHAs are a highly effective skincare ingredient with proven benefits, using them properly is imperative to getting good results.

What are AHAs?

AHAs are a group of water-soluble acids naturally occurring in dairy, sugarcane and fruits that chemically exfoliate the upper layer of the skin without the damage that is often associated with mechanical exfoliators or scrubs.

what does aha do
aha for skin

What do AHAs do?

Dermatologists often recommend using at least one Alpha Hydroxy Acid for its benefits in skincare. The exfoliating action of these acids encourages the shedding of dead skin cells and cell turnover, leading to improved skin tone and texture and even hydration, as they have been found to stimulate the production of collagen and hyaluronic acid.  

Used regularly, Alpha Hydroxy Acid and its benefits can reduce the appearance of acne scars and fine lines and reveal a brighter, smoother complexion*.

What are the different types of AHAs?

Different types of AHAs exist and several types of AHAs are often combined to draw on their slightly varying properties to create super effective exfoliating formulations. There are four main types of AHAs used in skincare:

  • Glycolic acid, which comes from sugarcane; it is the smallest form of AHA meaning it can penetrate deeper into the skin and is best to improve the appearance of acne scars, hyperpigmentation and fine lines if your skin can tolerate its potent exfoliant properties.
  • Lactic acid: present in dairy and fermented vegetables, it is a bigger, and therefore gentler, form of AHA which also acts as a humectant, attracting water to the skin, making it ideal for more sensitive and dry skin types.
  • Malic acid: derived from unripe fruits, mostly apples, it is a mild exfoliant as well as a humectant, like lactic acid, that can be used in lower concentrations (typically between 1–2%) to boost the efficacy of other AHA exfoliants.
  • Citric acid: extracted from citrus fruits, it is a slightly bigger molecule than glycolic acid and has astringent and antioxidant properties, which makes it a particularly great ally for oily skins combined with other acids.
AHA benefits

How to use AHAs safely

A mild tingling sensation is common when using AHAs due to their low pH, and overuse can cause dryness and irritation, so cycling out these products is advised. When using AHAs, avoid products containing vitamin C and retinol, as using more than one active ingredient at a time can lead to dryness, irritation, and breakouts. Always make sure to trial new active ingredients over a couple of weeks at least to see how your skin reacts and to slowly build up your skin tolerance to them.

AHAs should always be followed with ingredients that promote hydration and lock in moisture, such as Squalane, Hyaluronic Acid, and Ceramides. They can also increase photosensitivity**, so be sure to follow with sunscreen during the day.

what are ahas

How to incorporate AHAs into your routine

AHAs can be used as part of your daytime or nighttime routine but should be integrated into your skincare routine slowly in the form of a cleanser, toner or a serum, depending on your concerns. All three can be used in the morning to gently slough off any dead skin cells, while peels and masks, which often contain higher concentrations, are best used in the evening or as weekly treatments as they can be photosensitizing.

Whether you are already using an AHA as part of your regular routine, or you are new to this ingredient, there are a multitude of ways to incorporate this transformative active into your skincare lineup:

Example Product Title


The Everyday Cleanser

Formulated with a blend of natural fruit acids, this non-foaming cleanser gently exfoliates and hydrates to reveal a smoother, firmer, and more refreshed complexion.

Example Product Title


The Everyday Toner

This toner promises brighter, smoother skin in a swipe, thanks to a combination of  Glycolic, Lactic, and Phytic acid that exfoliates dead skin to stimulate cell turnover and reveal a natural glow.

Example Product Title


The Weekly Peel

This at home-peel improves texture and reduces signs of aging with a blend of Glycolic Acid and botanical Hyaluronic Acid. They work together to exfoliate and hydrate the skin. Use once a week on the face, neck, and décolleté, allowing the formula to work for 8-10 minutes before rinsing thoroughly.

Example Product Title


The Treatment

This multitasking product formulated with Lactic acid can be used as a spot treatment on blemishes, a facial scrub, or a 15 minute mask to bring new life to your complexion, smooth away dullness, clear pores, and increase cell turnover, giving you younger and more radiant looking skin.

*Tran D, Townley JP, Barnes TM, Greive KA. An antiaging skin care system containing alpha hydroxy acids and vitamins improves the biomechanical parameters of facial skin. Clin Cosmet Investig Dermatol. 2014 Dec 19

**Kays Kaidbey, Betsy Sutherland, Paula Bennett, Wayne G. Wamer, Curtis Barton, Donna Dennis, and Andrija Kornhauser, Topical glycolic acid enhances photodamage by ultraviolet light,Photodermatology, Photoimmunology and Photomedicine, vol. 19 (2003), issue 1, pages 21-27

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