Polyhydroxy acids are a type of chemical exfoliant, and are often thought of as the more gentle cousins of alpha hydroxy acids. They have similar effects on the skin but cause less irritation, so are good choices for those with sensitive skin.
What are polyhydroxy acids and what do they do?
Polyhydroxy acids are chemical exfoliants. They’re similar to alpha hydroxy acids, but as they have a larger molecular size and are absorbed into the skin more slowly, they’re much less irritating. They have exfoliating and anti-ageing properties, act as humectants to increase skin hydration, and have antioxidant properties. Gluconolactone and lactobionic acid are the two polyhydroxy acids most commonly found in skincare.
What are they used for?
Polyhydroxy acids are useful for skin brightening and smoothing, and improving the appearance of hyperpigmentation, acne, fine lines and wrinkles.
How should I use them?
Polyhydroxy acids are found in many products, including cleansers, toners, serums and moisturisers. Start using them just one to two times per week, and see how you tolerate them. They work well with most other active ingredients.
What are the key benefits?
Polyhydroxy acids are less irritating than alpha hydroxy acids, so are useful for those with sensitive skin and those who cannot tolerate alpha hydroxy acids. In addition, unlike alpha hydroxy acids, they don’t cause sun sensitivity.