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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
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 ↗
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
Pairs worth knowing
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