What it is
Cetearyl alcohol is a blend of the fatty alcohols cetyl alcohol and stearyl alcohol, predominantly the C16 and C18 chains. Despite the word alcohol, it behaves nothing like drying alcohols such as alcohol denat; its long, oil-soluble chains make it non-drying and skin-softening. In formulas it serves as an emollient, non-ionic emulsifier and emulsion stabilizer, thickener and viscosity controller, and opacifier, and it typically makes up a few percent of creams and lotions where it helps give body and a smooth feel.
Safety & warnings
Cetearyl alcohol is a fatty alcohol that is well tolerated by most skin types and is widely used even in products intended for sensitive skin; its long oil-soluble tail makes it non-drying, unlike volatile drying alcohols. As a fatty alcohol it can act as an occasional contact allergen for a small number of people, so those with known fatty-alcohol sensitivity should patch test, but most users have no issue.
Origin & sourcing
Cetearyl alcohol is a fatty (long-chain) alcohol blend that can be derived from vegetable sources such as coconut or palm oil, or produced synthetically. It consists chiefly of cetyl (C16) and stearyl (C18) alcohols and is supplied as a waxy solid that melts into the oil phase of a formula.
Questions everyone asks
Does cetearyl alcohol dry out skin?
No. It is a fatty alcohol whose long, oil-soluble chains make it non-drying and softening, which is different from drying alcohols like alcohol denat.
What is it used for in sunscreen?
It acts as an emollient, thickener, and emulsion stabilizer, helping give the cream body, a smooth feel, and a stable oil-water blend.
What is cetearyl alcohol made of?
It is a blend of cetyl and stearyl alcohols, fatty alcohols that can be sourced from vegetable oils such as coconut or palm, or made synthetically.