Glossary

Hyaluronic Acid (Term)

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Hyaluronic Acid (Term) — a naturally occurring molecule in the skin belonging to the glycosaminoglycan family, known for its remarkable ability to hold water. It helps keep the skin hydrated, plump, and cushioned, and is a widely used humectant in skincare formulations.

Key points

  • Hyaluronic acid can bind a large amount of water relative to its weight, supporting skin hydration.
  • It occurs naturally in the dermis and extracellular matrix, where it helps maintain moisture and volume.
  • In skincare it acts as a humectant, drawing water into the upper layers of the skin.
  • It is available in different molecular weights, which can affect how it behaves on and within the skin.

Frequently asked

Is hyaluronic acid an exfoliating acid like glycolic acid?

No; despite the name, hyaluronic acid is a hydrating humectant rather than an exfoliating acid, and it does not chemically exfoliate the skin.

How does hyaluronic acid hydrate the skin?

It works as a humectant, attracting and binding water into the upper layers of the skin to help it feel more plump and hydrated.

Related topics

This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.

Encyclopedia

Further reading

This entry was written and checked against the sources below. They are published by clinical and scientific bodies, they are listed most readable first, and each one opens in a new tab. They are background for the whole entry rather than footnotes to individual sentences.

  1. Hyaluronic Acid in Topical Applications: The Various Forms and Biological Effects of a Hero Molecule in the Cosmetics Industry PubMed Central Peer-reviewed, open access pmc.ncbi.nlm.nih.gov
  2. Recent Advances of Hyaluronan for Skin Delivery: From Structure to Fabrication Strategies and Applications PubMed Central Peer-reviewed, open access pmc.ncbi.nlm.nih.gov
  3. Efficacy Evaluation of a Topical Hyaluronic Acid Serum in Facial Photoaging PubMed Central Peer-reviewed, open access pmc.ncbi.nlm.nih.gov
  4. The 24-hour skin hydration and barrier function effects of a hyaluronic 1%, glycerin 5%, and Centella asiatica stem cells extract moisturizing fluid: an… PubMed Central Peer-reviewed, open access pmc.ncbi.nlm.nih.gov
  5. Benefits of topical hyaluronic acid for skin quality and signs ... PubMed Peer-reviewed (abstract) pubmed.ncbi.nlm.nih.gov
  6. Hyaluronic Acid in Topical Applications: The Various Forms and Biological Effects of a Hero Molecule in the Cosmetics Industry PubMed Peer-reviewed (abstract) pubmed.ncbi.nlm.nih.gov

SYNC does not publish medical advice. Nothing here replaces a consultation with a doctor or a pharmacist about your own skin.