LHA helps promote skin cell turnover, exfoliating the top layer of dead skin cells to expose the newer, brighter-looking cells underneath. This leaves the surface looking and feeling smooth. Its mild exfoliating action allows users to apply it daily.

Lipohydroxy acid is a derivative of salicylic acid, which means it has a similar chemical structure and works similarly, but with its own unique properties. LHA is more lipophilic than salicylic acid, so it dissolves better in oils and lipids—good for clogged pores. It isn't as effective at penetrating the skin though, and does so more slowly, making it better tolerated by mild acne-prone skin and more able to evenly exfoliate skin cells from the surface.

Capryloyl salicylic acid is another name for lipohydroxy acid (LHA). Its chemical structure allows it to dissolve more easily in lipids than other salicylic acids.

Yes, lipohydroxy acid can be used with vitamin C. These two ingredients work synergistically to exfoliate and promote a more even skin tone, texture and radiant complexion.

Whether one is better than the other really comes down to the skin concern you are trying to address. Both dissolve in oils and sebum (natural skin oils) so are able to penetrate sebum-rich sebaceous glands. But lipohydroxy acid is more lipophilic than salicylic acid, and so more soluble in oils and lipids. It's also a larger molecule than salicylic acid, giving it slower and less deep skin penetration. This makes it better tolerated by blemish-prone skin.

Although it's a gentle exfoliant, and both skincare ingredients can be used to address blemish and ageing concerns, SkinCeuticals advises caution before combining LHA with retinol. If you decide to do so, introduce each to your skin slowly, at lower concentration and reduced frequency, and work up to a staggered application at different times, preferably on alternate nights, whilst your skin builds its tolerance levels.

As a general rule, SkinCeuticals recommends using a chemical exfoliant around three times a week. However, the mild exfoliating action of LHA allows users with tolerant complexions to apply it daily without stripping the skin, and providing you build up to that frequency slowly.

Although the gentle exfoliating effect of LHA results in thinning of the outermost layer of the skin, it is also associated with thickening of the dermis, a deeper layer. This anti-ageing effect is thought to be the result of increasing the levels of hyaluronic acid and the structural skin proteins; collagen and elastin.

No. Same-same, but different! Although both are used in skincare as chemical exfoliants, LHA is a derivative of salicylic acid, a Beta hydroxy acid (or BHA), and AHAs (Alpha hydroxy acids) are a separate group with similar but not identical properties.