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Po

Polyglutamic Acid

Polyglutamic Acid · Sodium PolyglutamateHydrator

A fermented ingredient that holds water in a film on skin, better than glycerin alone in tests.

What it does

It’s made by the same fermentation that makes natto, and forms a film on skin that held water noticeably better than glycerin in side-by-side tests. It’s often paired with hyaluronic acid, which sinks in a little while this stays on the surface.

The EU’s ingredient database lists it as a skin conditioner, its general term for an ingredient that keeps skin in good condition.European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗

The evidence, graded

strongOne application of a ceramide cream lowered water loss through the skin, measured from two hours and held to 24 hours, and raised skin hydration over the same day. Hyaluronic acid creams improved skin hydration and elasticity when measured at 30 and 60 days. Neither source Drop has read measured how long barrier repair takes, so Drop sets no barrier-repair window.Pavicic 2011 · Journal of Drugs in Dermatology ↗

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Also known as

PGA

Pairs worth knowing

Hyaluronic Acid · works together ↗Glycerin · works together ↗Niacinamide (Vitamin B3) · works together ↗Panthenol (Pro-vitamin B5) · works together ↗

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