Hyaluronic acid was first isolated in 1934 from the vitreous humor of a cow's eye by two biochemists at Columbia University, Karl Meyer and John Palmer.

Its name comes from the Greek hyalos, meaning "glass," a nod to the transparency of the gel it forms. It wasn't until the 1990s that biotechnology made it possible to produce it through fermentation, with no animal origin, turning it into one of the most widely used hydrating actives in cosmetics.

Our skin naturally produces it, but that production declines with age: by 50, the dermis holds roughly half as much as it did at 20¹. Which is why it helps both to supply more of it and to support what skin still makes on its own.

In the dermis, hyaluronic acid fills the space between collagen and elastin fibers. It holds water there, maintains tissue volume and elasticity, and facilitates exchanges between cells¹. In joints, it lubricates cartilage; in the eye, it maintains the shape of the eyeball.

Its lifespan is very short: skin continuously renews it, which makes it sensitive to anything that slows that production — UV, smoking, pollution, aging.

Molecule size changes everything. A high molecular weight hyaluronic acid stays at the surface and hydrates by forming a film; a low molecular weight form penetrates the epidermis and works more deeply^2,3. Our formulas combine both.

• Concentrated hydrating serums, applied under your cream;
• Day and night creams and fluids;
• Plumping masks for an instant glow boost;
• Smoothing eye contours;
• Redensifying anti-aging treatments.

1. On damp skin
   Hyaluronic acid captures the water available: apply your serum right after your toner, while skin is still damp.
2. Seal it in
   Follow with a cream: it keeps the captured water from evaporating and extends the plumping effect.
3. Morning and night
   With no contraindication, it's used year-round and pairs with every other active, vitamin C and fruit acids included.

Stable and only mildly light-sensitive, hyaluronic acid keeps well. Simply keep your bottle closed and follow the period-after-opening guidance.

It's identical to what skin produces naturally, which explains its excellent tolerance: no known contraindication for topical use, including during pregnancy and breastfeeding, and it suits sensitive skin⁴. A tip for very dry climates: never apply it alone without a cream on top, or it could draw water from your skin instead of the air.