What is hydroxyacetophenone in skincare?
Hydroxyacetophenone – usually 4-hydroxyacetophenone on a label – is a phenolic compound used mainly as an antioxidant and a preservative booster. It has little antimicrobial power on its own, but it makes preservatives like phenoxyethanol work harder, so formulators can use less of them.
It also stabilises the formula itself, slowing the oxidation that turns oils rancid and degrades delicate actives. That combination is why it turns up in so many otherwise minimal ingredient lists.
What skin concerns does hydroxyacetophenone treat?
It is chiefly a formulation ingredient rather than a treatment, but it is not inert. As an antioxidant it contributes to the free-radical defence of a product, and it has documented soothing activity on irritated skin.
More interestingly, laboratory work shows 4-hydroxyacetophenone acts as an antipigmentation agent by inhibiting tyrosinase, the key enzyme in melanin production – a secondary benefit for uneven tone, though not a reason to buy a product on its own.
What ingredients are best paired with hydroxyacetophenone?
It is almost always formulated with phenoxyethanol, caprylyl glycol or ethylhexylglycerin, whose preservative effect it amplifies.
It is well tolerated by most people, though allergic contact dermatitis has been reported in isolated cases, including a photo-aggravated reaction to it in a sunscreen. If you get unexplained reactions to products that share few other ingredients, it is worth noting as a candidate for patch testing. Take our Skin Quiz.
What is dry skin?
Dry skin – xerosis in clinical terms – is a skin type that lacks oil rather than water. It feels tight after cleansing, looks flaky or rough, may show fine cracking, and often reads dull because the uneven surface scatters light.
It is worth separating dry skin from dehydrated skin: dryness is a lack of lipids and is usually lifelong, while dehydration is a temporary lack of water and can happen to oily skin too. Many people have both at once.
What causes dry skin?
At the root is a compromised moisture barrier. When ceramides, cholesterol, fatty acids and natural moisturising factors run low, water evaporates out of the skin faster than it can be replaced.
Age, genetics, cold weather and low humidity, long hot showers, harsh surfactants, over-exfoliation, some medications, and conditions such as eczema and psoriasis all deplete those lipids. Consistent moisturising is the single intervention with the strongest evidence behind it.
What ingredients are best for dry skin?
Rebuild in layers. Humectants such as hyaluronic acid, glycerin, urea and panthenol draw water in; emollients such as squalane, jojoba oil and shea butter smooth the surface; and occlusives seal the whole thing in.
Ceramides, cholesterol and fatty acids are the priority, because they replace exactly what a dry barrier is missing, with niacinamide helping the skin make more of its own. Apply to damp skin, and swap foaming cleansers for cream or oil-based ones. Take our Skin Quiz to find the right combination for your skin.
