Cited skincare — every flag names its source, no upsell.

Aluminum Hydroxide

A mineral coating for sunscreen particles and pigments — helps them spread smoothly without clumping.

What it does

A fine mineral powder used mostly to coat titanium dioxide, zinc oxide and pigments. The coating helps the particles spread smoothly, clump less and sit better on skin.

The EU’s ingredient database lists it as an emollient (gives skin a soft, smooth look), a thickener (controls how thick the product is) and an opacifier (makes the product less see-through).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗

The evidence, graded

expert consensusUS safety reviewers (2016) assessed alumina and aluminum hydroxide, which they stress are not the same as aluminum metal. They list aluminum hydroxide’s jobs as buffering, preventing corrosion and adjusting pH. They found no believable evidence linking these ingredients to Alzheimer’s disease or breast cancer. Both barely dissolve in water, so the body doesn’t take them up, and they don’t irritate skin. They judged both safe as used.Becker 2016 · 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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