What it is
Hyaluronic acid (HA) is a naturally occurring polysaccharide found throughout the body — particularly in joints and skin. It is one of the most effective humectants used in skincare.
How it works
HA molecules attract and hold water — up to 1,000× their weight in water molecules. Applied to skin, lower-molecular-weight HA penetrates the upper layers; higher-molecular-weight HA forms a moisture-retaining film on the surface.
Best for
- ✓All skin types — especially dry or dehydrated skin
- ✓Layering under moisturizers to boost hydration
- ✓Plumping fine dehydration lines
- ✓Post-procedure skin that needs gentle hydration
Use with caution if
- —Very dry climates: HA may pull moisture from deeper skin layers if no occlusives are layered on top. Always seal with a moisturizer.
Layering notes
Apply to slightly damp skin for best results. Always follow with a moisturizer to lock in the water HA attracts. Pairs with essentially every other ingredient.
This content is informational and does not replace professional dermatological consultation. Results may vary.
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