C
C20-40 Alkyl Stearate
C20-40 Alkyl StearateBarrier
Stearic acid joined to long fatty alcohols, used to condition and thicken.
What it does
It’s stearic acid joined to long-chain fatty alcohols, which makes a wax. The EU lists it to condition skin and to thicken.
The EU’s ingredient database lists it as a thickener (controls how thick the product is).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗
The evidence, graded
expert consensusUS safety reviewers (2015) looked at 237 similar esters and judged them safe as cosmetics use them, provided the product is made not to irritate. Where an ester had no data, they used data on similar ones in the group. Their list names ethylhexyl olivate, ethylhexyl hydroxystearate and C20–40 alkyl stearate, and their index lists cetearyl olivate under that report.Fiume 2015 · International Journal of Toxicology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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