Po
Polyglutamic Acid
Polyglutamic Acid · Sodium PolyglutamateHydrator
Polymer humectant from natto fermentation. Holds several times its weight in water; pairs naturally with hyaluronic acid.
What it does
Polyglutamic acid is a high-molecular-weight humectant produced by the same Bacillus subtilis fermentation that makes natto. It forms a hydrating film on the skin that holds water meaningfully better than glycerin alone in side-by-side measurements. Often paired with hyaluronic acid for complementary depth — HA penetrates a bit, PGA stays mostly on the surface. Common in K-beauty hydrating serums.
The evidence, graded
strongNiacinamide reduces transepidermal water loss while hyaluronic acid adds hydration. They work well in the same routine and are commonly co-formulated.Bissett 2002 · Cutis ↗
strongHydrating ingredients (hyaluronic acid, glycerin) show immediate plumping and dewy-finish effects within minutes. Barrier-repair products (ceramides, panthenol, niacinamide-as-barrier) show measurable improvement in 1-2 weeks.Pavicic 2011 · Journal of Drugs in Dermatology ↗
expert consensusThe traditional K-beauty 10-step layering approach (oil cleanser → foam cleanser → toner → essence → serum → ampoule → sheet mask → eye cream → moisturizer → SPF) is fully compatible with Western actives but not necessary for results. Adding more steps does not equal more efficacy.Draelos 2018 · Journal of Cosmetic 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
This page is public and indexed on purpose (unlike profiles and drops, which are unlisted) — it’s the citation behind shared ingredient cards, and it should be findable.
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