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Magnesium Stearate
Magnesium Stearate
A powder binder — holds pressed powders together, helps them stick to skin, and adds a smooth, slippery feel.
What it does
A soft white powder made from stearic acid and magnesium. It holds pressed powders together, helps them stick to skin, and adds a smooth, slippery feel.
The evidence, graded
expert consensusUS safety reviewers (2019) assessed 102 fatty acids and their salts, used mostly to stop caking, steady mixtures or thicken. Their list names behenic, arachidic and isostearic acid and magnesium, sodium and aluminum stearate. Behenic acid is used at up to 14% in lipstick, magnesium stearate at up to 7.2% in face powders. Some can irritate skin, and the less stable fatty acids can break down into compounds that cause allergy. So products must be made not to irritate or cause allergy.Burnett 2019 · Cosmetic Ingredient Review ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Browse all 1238 ingredients — grouped by what they do, each with whatever evidence we can cite.
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