Hyaluronic Acid
Multi-weight humectant — the most recognised hydration ingredient in modern skincare
Function in skin biology
Hyaluronic acid (HA) is a glycosaminoglycan naturally present throughout the body, including the dermis, where it holds water within the extracellular matrix. In cosmetic formulation, HA's molecular weight determines its behaviour: high-molecular-weight HA sits on the skin surface and forms a hydrating film, while low-molecular-weight HA penetrates further into the upper skin layers. Many modern formulas combine multiple molecular weights for layered hydration.
Why Ambernay evaluates it
HA is evaluated for inclusion where a formula objective calls for an additional humectant layer beyond glycerin and panthenol — particularly in formulas targeting visibly dehydrated or fine-line-prone skin. Sourcing matters: biofermented HA (produced via bacterial fermentation rather than animal extraction) is the cosmetic industry standard and the form Ambernay evaluates.
Where concentration matters
Cosmetic HA is typically formulated between 0.1% and 2%. Because HA can hold many times its weight in water, even low concentrations contribute meaningfully to hydration feel. Multi-molecular-weight blends are generally associated with more complete hydration performance than single-weight HA alone.
What we do not claim
We do not claim that topical hyaluronic acid replicates the effects of dermal filler injections, restores lost facial volume or has any structural/volumising effect beneath the skin surface. Topical HA is a surface and upper-epidermis humectant — not a volumising treatment.
Best paired with
HA is most effective applied to slightly damp skin and sealed with an emollient or occlusive layer immediately after — applied to fully dry skin in a low-humidity environment, humectants including HA can pull moisture from the skin itself rather than retain it.
Claim caution / regulatory note
Hyaluronic acid is a cosmetic humectant. Claims must remain within cosmetic function: surface hydration, visible plumping of fine dehydration lines, comfort. Claims of dermal filling, wrinkle elimination or structural change are not permitted for a topical cosmetic.