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Magnesium Sulfate
Magnesium Sulfate
Epsom salt, used here as a texture and stability aid — a pinch locks water-in-oil creams together and controls how thick they are.
What it does
In creams where water droplets sit inside oil, a little of it helps hold the cream together and controls how thick it is. It’s there for texture and stability, not for skin.
The evidence, graded
expert consensusUS safety reviewers (2018) say products use magnesium sulfate to add bulk, at up to 11% in leave-on products and 25% in rinse-off ones. From many patch tests, they say magnesium salts don’t tend to cause allergy. A 50% solution didn’t irritate mouse skin. They judged it safe as used.Johnson 2018 · International Journal of Toxicology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
epsom salt
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