Gentle exfoliation is replacing the strong stuff

What are the different types of exfoliant?

There are three types of exfoliant: physical, chemical and enzyme. Physical exfoliants are scrubs and cloths, which work on the surface and are easy to overdo, particularly the gritty ones. Chemical exfoliants loosen the bonds between dead cells, and the FDA's guide to alpha hydroxy acids notes that how much they exfoliate depends on the acid, its strength, its pH and the rest of the formula. Alpha hydroxy acids such as glycolic and lactic work on the surface; beta hydroxy acid, which in cosmetics is most often salicylic acid, is oil-soluble and works inside the pore. Polyhydroxy acids are larger molecules that penetrate more slowly, and a 2004 review of polyhydroxy acids describes them as giving similar effects to alpha hydroxy acids without the same stinging, which is why they suit sensitive skin. Enzyme exfoliants, usually from fruit, are generally the mildest.

Why are gentler exfoliants like mandelic acid and PHAs popular now?

Gentler exfoliants are popular because the strong ones left a lot of people with shiny, sensitised skin. The FDA's record of complaints about alpha hydroxy acid products found that the more serious reactions came mostly from the products that exfoliate hardest, such as skin peelers. The current preference for mandelic acid, PHAs and enzymes is a correction. Mandelic acid has a larger molecule than glycolic, so it goes in more slowly and tends to sting less, and in a small 2020 trial mandelic acid peels caused fewer side effects than salicylic acid peels. That makes it a reasonable starting point on darker skin tones, where irritation more readily leaves a dark mark.

How often should you exfoliate your face?

Most people need to exfoliate far less often than product labels suggest, and some skin does well on none at all. A sensible way to start is the one the British Association of Dermatologists suggests for skin treatments that can irritate: once or twice a week at first, building up only if your skin is comfortable. If you use a retinoid, that is already clearing dead cells from the surface, so exfoliating acid on top is usually unnecessary. Signs you have overdone it: tightness, shine that looks like a burn rather than a glow, stinging from products that never stung, and new sensitivity. A MyAgenix read shows where an exfoliant fits in your routine, or leaves it out.

Who should not use exfoliating acids or scrubs?

Anyone in an eczema flare, anyone with active rosacea, and anyone whose barrier is already unhappy should skip exfoliation. The NHS advice for rosacea is to use gentle skincare for sensitive skin, and the BAD advises people with atopic eczema to avoid irritants that inflame the skin. Exfoliation is the first thing to stop and the last thing to bring back. There is more on this in our pieces on rosacea and eczema.

General information about skin, not medical advice. MyAgenix offers cosmetic guidance to help you choose products. It does not diagnose or treat any condition. For anything that needs treating, see a pharmacist, your GP or a dermatologist.