Many people are familiar with acid categories like Alpha Hydroxy Acids (AHAs) and Beta Hydroxy Acids (BHAs) – but there’s a new generation of AHAs that are worth exploring called Polyhydroxy Acids. Polyhydroxy Acids (often abbreviated to PHAs) can deliver some of the same skincare benefits (like exfoliating and visible brightening) as AHAs but have a few key differences, including that they may be gentler and less irritating on skin. They also have smoothing properties, working well on dry skin.
What is Polyhydroxy Acid?
Polyhydroxy acids are a type of acid – like Alpha Hydroxy Acids long used in skincare – but unlike traditional AHAs, they have multiple hydroxy groups. These molecules can work as a humectant — thus giving them moisturizing properties. PHAs also generally have a larger molecule size compared to AHAs and BHAs, which allows them to penetrate the skin more slowly. This is another reason PHAs can be great options for sensitive skin types looking to get the benefits of exfoliation and brightening, because they may reduce the tingling, burning, or redness some users can experience. Lactobionic acid for example has also been shown to be gentle on the skin and doesn’t cause the burning and irritation which are sometimes associated with certain AHAs.
What are the different types of Polyhydroxy Acids?
PHAs are the collective name of different types of Polyhydroxy Acids. Two of the most popular Polyhydroxy Acids include Lactobionic Acid and Gluconolactone.
How do Polyhydroxy Acids compare to BHA and AHAs?
Beta Hydroxy Acids and Alpha Hydroxy Acids are undoubtedly two of the most popular types of acids in skincare and they’re known for their exfoliating properties (think Salicylic Acid and Glycolic Acid). Much like these acids, PHAs can help to exfoliate the skin for visibly smoother and brighter skin but PHA ingredients like Lactobionic Acid and Gluconolactone have a larger molecule size than some other types of acids so they are often better tolerated on the skin and can be tolerable for sensitive skin. PHAs also have additional humectant and moisturization properties compared with AHAs, which may sometimes be drying on the skin.
What do Polyhydroxy Acids do for Skin?
When you hear of a new skincare ingredient, you are obviously going to want to know what it actually does for skin and what are the benefits? Polyhydroxy acids (PHAs) are ingredients known for their antioxidant, humectant, and exfoliation properties.
Polyhydroxy Acids for Exfoliating: PHAs like Gluconolactone and Lactobionic Acid are often used for exfoliating the skin and have mild exfoliating properties which can be suitable for sensitive and dry skin.
Polyhydroxy Acids to Help Support the Skin’s Moisture Barrier: Polyhydroxy Acids are also humectant ingredients. Humectants help to attract water to the skin to help with skin hydration. By helping to hydrate skin, PHAs have been shown to help reinforce the skin’s barrier function. 6 Gluconolactone in particular has been shown to strengthen and seal the skin moisture barrier, which can help reduce transepidermal water loss and improve the look of signs of aging.
Polyhydroxy Acids and Antioxidant Benefits: Many PHAs, including Gluconolactone, have antioxidant properties, meaning they can help with scavenging free radicals.
Polyhydroxy Acids for Skin Tone: PHAs can also help to visibly improve skin tone. Skincare products containing Gluconolactone have been shown to visibly improve dark spots and skin tone in addition to making skin look brighter and more luminous.
Polyhydroxy Acids for Skin Texture: Lactobionic Acid has been proven to show skin smoothing benefits.
Polyhydroxy Acids for Sensitive Skin: Thanks to their larger molecule weight which allows for slower absorption, PHAs can be suitable for sensitive skin types; in fact, PHAs have been found to be compatible with sensitive skin in clinical studies.
What products contain Polyhydroxy Acids?
Our Clarifique Pro-Solution Serum is powered by 10% PHA (gluconolactone) in addition to niacinamide, and beech bud extract. With its 10% PHA concentration Clarifique Pro-Solution strikes the perfect balance between results and comfort. Some concentrated brightening serums formulated with AHA or BHA may cause sensations like burning or tingling when applied, but PHA has a larger molecular structure compared to AHA or BHA, allowing it to gently exfoliate the surface of the skin to minimize irritation. Clarifique is our brightening serum that visibly reduces dark spots and post-acne marks and tightens the look of pores.
Ingredient Compatibility with Polyhydroxy Acids
Many skincare products feature a variety of ingredients or your skincare routine may contain a variety of different products like Vitamin C or Hyaluronic Acid, which begs the question: what ingredients work well with PHAs?
PHA and Retinol: Creams containing PHAs and Retinoids (specifically retinyl acetate, also known as pro-vitamin A) have been shown to have anti-aging benefits like smoothing and plumping.
PHA and Vitamin C: Vitamin C is often known for its antioxidant benefits and visible brightening effects. In one study, a serum formulated with Vitamin C and Gluconolactone was shown to have significant skin brightening benefits.
Skincare Ingredient Guides
Read below our other guides to ingredients in your skincare.
Shop the Selection
5 This characteristic allows them to penetrate the skin more slowly, which is another reason it's gentler and a good option for the sensitive skin; in fact, it avoids tingling, burning, or redness. https://onlinelibrary.wiley.com/doi/10.1111/jocd.15215
14 Lactobionic acid represents a new generation of AHA that has a polyhydroxyl structure (so-called polyhydroxyl acid); it has been proven to provide structural and smoothing benefits to the skin, thus providing multiple anti-aging advantages.