Humectants, emollients and occlusives: how moisturisers work
Most moisturisers combine three groups of ingredients that each do a different job. Here is how to recognise them on an INCI list and what they can and cannot do.
Updated: 31 October 2026 · Reviewed by: Kamil Pyziak
Three jobs in one cream
A moisturiser is rarely built around a single “hydrating” ingredient. Formulators usually combine three groups: humectants that attract and hold water, emollients that soften and smooth the skin surface, and occlusives that form a film and slow down water loss from the skin.
The balance between these groups largely decides how a product feels: a light gel is often rich in humectants, while a thick balm relies more on emollients and occlusives. Reading the list with these three roles in mind tells you more than any marketing claim on the front of the pack.
Humectants: ingredients that bind water
Humectants are small or water-loving molecules that attract water. Typical INCI names include Glycerin, Propanediol, Butylene Glycol, Sodium PCA, Urea, Betaine, Panthenol, Sorbitol and Sodium Hyaluronate (a salt of hyaluronic acid).
Glycerin is the most common and one of the best studied. Hyaluronic acid and its salts bind water too, but they are usually used at low levels. Urea has a dual character: at low levels it acts as a humectant, at higher levels it also softens rough, thickened skin. The label does not tell you which level a product uses.
Emollients: softness and slip
Emollients fill the small gaps between skin flakes and make the surface feel smoother. They include plant oils and butters (Simmondsia Chinensis Seed Oil, Butyrospermum Parkii Butter), esters (Caprylic/Capric Triglyceride, Isopropyl Myristate, Coco-Caprylate/Caprate), Squalane and fatty alcohols such as Cetearyl Alcohol.
Esters with long, branched chains tend to feel light and dry quickly; butters and heavier oils feel richer. Whether a particular emollient suits oily or blemish-prone skin depends on the whole formula and the individual; INCI lists cannot predict that reliably.
Occlusives: a film against water loss
Occlusives form a thin layer on the skin and reduce transepidermal water loss. The classics are Petrolatum, Paraffinum Liquidum (mineral oil), Cera Microcristallina, Lanolin, beeswax (Cera Alba) and silicones such as Dimethicone.
Cosmetic-grade mineral oils and petrolatum are highly refined; their safety in cosmetics is assessed under EU rules. Silicones like dimethicone form a breathable film rather than an airtight seal. Some people prefer products without these ingredients for personal reasons – that is a matter of preference rather than safety.
Ingredients that do more than one job
Many ingredients sit between the groups. Shea butter is both an emollient and mildly occlusive. Dimethicone is an emollient and an occlusive. Panthenol is a humectant and a conditioning agent. Ceramides (Ceramide NP, Ceramide AP), cholesterol and fatty acids are often combined to resemble the lipids of the skin barrier.
That is why functions listed in CosIng – such as “humectant”, “skin conditioning” or “emollient” – are a useful guide, but not a strict classification.
How to read a moisturiser’s INCI
Look at the first five to ten ingredients: that is where most of the formula is. Water (Aqua) usually comes first, followed by humectants and emollients. Occlusives such as petrolatum near the top suggest a rich, protective product; humectants high up with few oils suggest a light, gel-like texture.
Ingredients present at 1% or less may appear in any order after those above 1%, so a “star” active listed near the end may be present in a very small amount – or not. The list alone does not reveal it.
What the label does not tell you
An INCI list shows which ingredients are present, not how much of each, how they were combined or how the product was tested. Two creams with similar lists can feel and perform quite differently.
If your skin is very dry, cracked or irritated for a longer time, it is worth talking to a pharmacist or a doctor; a moisturiser supports the skin, but it is not a treatment.