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Sodium PCA
Sodium PCAHydrator
Naturally present in skin's NMF. Pulls water into the upper skin layers as effectively as glycerin.
What it does
Sodium PCA is a component of the skin's natural moisturizing factor (NMF) — the mix of small humectant molecules in the stratum corneum that keep the surface flexible. As a topical humectant it performs comparably to glycerin and is a common back-pocket pick when formulators want NMF-aligned hydration. Generally tolerated by sensitive skin.
The evidence, graded
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 ↗
emergingNiacinamide reduces transepidermal water loss while hyaluronic acid adds hydration. They work well in the same routine and are commonly co-formulated.Bissett 2002 · Cutis ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
sodium pyrrolidone carboxylate
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