La
Lactose
LactoseHydrator
Milk sugar, used to hold water at the skin’s surface.
What it does
It’s the natural sugar in milk, made of glucose and galactose. Products use it as a humectant, an ingredient that holds water at the skin’s surface.
The evidence, graded
expert consensusUS safety reviewers (2019) assessed 25 sugars and related ingredients used in cosmetics; their index lists trehalose, glucose, sucrose, fructose, isomalt and rhamnose under that report, and its conclusion list names lactose, the sugar in milk. They say these are most often used to condition skin, and also to hold water or add flavor. Many are everyday food sugars, and they judged all 25 safe as used in cosmetics.Fiume 2019 · 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
milk sugar
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