What is glycerin in skincare?
Glycerin, also called glycerol, is a clear, odourless humectant found naturally in skin lipids and produced commercially from plant oils or by synthesis. It is one of the most widely used ingredients in cosmetics, and one of the best studied.
It draws water into the stratum corneum and holds it there, and it also helps regulate how skin cells mature and shed. Research on glycerol and the skin shows it does considerably more than simply attract moisture.
What skin concerns does glycerin treat?
It relieves dryness, tightness and flaking in every skin type, and it improves barrier function measurably – a controlled study of 20% glycerin cream found gains in both hydration and barrier properties.
It is gentle enough for eczema-prone, sensitive and post-procedure skin, and light enough for oily and acne-prone skin. It also softens the feel of fine lines by plumping dehydrated cells.
What ingredients are best paired with glycerin?
It works best in the classic humectant-emollient-occlusive sequence: glycerin and hyaluronic acid to draw water in, ceramides and squalane to hold the barrier together, and a richer occlusive on top if skin is very dry.
Glycerin also makes exfoliating acids and retinoids far more tolerable. Unlike hyaluronic acid it performs reliably even in low humidity, which is why it remains the workhorse humectant in most formulations. 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.
