What it is
Isocetyl stearoyl stearate is a branched-chain ester formed from isocetyl alcohol and stearoyl stearate-type fatty acid components. It is an emollient that spreads readily and leaves a soft, non-greasy, cushioned feel, and it can help disperse pigments and UV filters in a formula. In sunscreens it contributes to texture and skin feel rather than to UV protection.
Safety & warnings
Emollient esters of this type are generally well tolerated and are not recognized as common allergens. As a fatty ester, it may have some pore-clogging potential for individuals very prone to comedones, though it is widely used in facial products.
Origin & sourcing
Synthetic ester derived from fatty alcohol and fatty acid components.
Questions everyone asks
What does this ester do in sunscreen?
It is an emollient that improves spreadability and skin feel and can help disperse pigments and UV filters; it is not itself a UV filter.
Is it natural or synthetic?
It is a synthetic ester made from fatty alcohol and fatty acid building blocks.