What Is an Emollient?
An emollient is a moisturising ingredient that softens and smooths skin by filling in the microscopic gaps between skin cells — the cracked "mortar" between the corneocyte "bricks" of the stratum corneum. Unlike humectants (which attract water) or occlusives (which form a physical barrier on top), emollients integrate into the lipid matrix to restore smoothness and flexibility from within. The result is skin that feels softer, appears less rough, and has improved barrier integrity.
How Emollients Work
The stratum corneum lipid lamellae consist of ceramides, cholesterol, and fatty acids in a precise lamellar arrangement. When barrier function is compromised, these lipids are depleted or disorganised. Emollient ingredients — typically fatty acids, oils, or esters — intercalate into this matrix, restoring the ordered lipid structure and improving barrier cohesion.
Common Emollient Ingredients
Plant oils (squalane, jojoba, rosehip), fatty alcohols (cetyl, stearyl, cetearyl alcohol), fatty acids (linoleic acid, oleic acid), shea butter, and synthetic esters (isopropyl isostearate, ethylhexyl stearate) all function as emollients. Different types have different textures — from dry-finish squalane to richer shea butter — allowing formulation for different skin types.
Moisturiser anatomy: Most complete moisturisers combine all three types: a humectant (e.g. glycerin) to attract water, an emollient (e.g. squalane) to smooth, and an occlusive (e.g. dimethicone) to seal. Each serves a distinct mechanical role.
See Humectants and Lipid Barrier.