Hy
Hyaluronic Acid
Sodium Hyaluronate · Hyaluronic Acid · Hydrolyzed Hyaluronic Acid · Potassium HyaluronateHydrator
The moisture-puller in hydrating serums: it holds water in skin’s top layer.
What it does
It’s a sugar your skin already makes, and it holds onto water. On skin it pulls water to the surface; in dry air it pulls from deeper skin, which can leave you drier.
The evidence, graded
strongIn a 4-week double-blind trial, 36 nursing-home residents aged 60 to 80 with dry skin used three lotions on three spots on the leg: one with small-molecule (low molecular weight) hyaluronic acid, one with large-molecule hyaluronic acid, and the same lotion without either. The small-molecule lotion raised skin moisture more than the other two. Water loss and dryness symptom scores did not differ between them.Muhammad 2024 · Archives of Dermatological Research ↗
emergingFine together, in any order — in one study, niacinamide on dry skin raised the fats in the skin’s outer layer and cut the water the skin lost. Hyaluronic acid is the molecule skin itself uses to hold water.Tanno 2000 · British Journal of Dermatology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
HA
Pairs worth knowing
Read more
How Drop works · 5 minHow to Read Percentage Claims on Skincare ProductsPercentage claims only mean something in context: effective range, formulation pH, molecular form, and whether the dose exceeds the saturation point.Routines · 5 minSkincare for the Gym: Before, During, and After SweatSweat plus sunscreen plus friction is a recipe for breakouts and irritation. Here is what to do before a workout, during, and after to keep skin clear.How Drop works · 5 minWhen Cheaper Skincare Products Work Just as WellDrugstore ceramide moisturizers and niacinamide serums often match luxury equivalents. Where premium pricing is justified is narrower than marketing implies.
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