Sodium hyaluronate is a substance frequently incorporated into a wide range of skincare and medical products. It is the salt form of hyaluronic acid, a molecule naturally present in human connective tissues. The primary function of sodium hyaluronate is to attract and hold onto water, making it a powerful hydrating agent.
Differentiating from Hyaluronic Acid
Sodium hyaluronate and hyaluronic acid are not identical. Sodium hyaluronate is the sodium salt derived from hyaluronic acid, a chemical distinction that results in a molecule with a lower molecular weight. This smaller size allows it to penetrate deeper into the skin’s layers compared to the larger hyaluronic acid molecule, which tends to work more on the surface.
This structural difference also contributes to its stability. Sodium hyaluronate is less susceptible to oxidation, the chemical degradation that can occur when substances are exposed to air. This enhanced stability makes it a reliable ingredient in cosmetic formulations with a longer shelf life. Furthermore, sodium hyaluronate is water-soluble, which allows it to be easily incorporated into a wide variety of water-based serums and creams.
Common Applications
The properties of sodium hyaluronate lead to its use in several distinct applications, primarily in skincare and medicine. In topical skincare, it functions as a humectant in products like serums, moisturizers, and masks. As a humectant, it draws moisture from the environment into the skin, which helps to temporarily reduce the appearance of fine lines and gives the skin a plumper, more hydrated look.
Beyond cosmetics, it has significant medical uses. In ophthalmology, sodium hyaluronate is a component in lubricating eye drops designed to treat dry eye syndrome. Its viscoelastic nature helps stabilize the tear film on the cornea, providing lasting relief from dryness. In orthopedics, it is used in intra-articular injections to treat osteoarthritis, particularly in the knee. It supplements the natural synovial fluid, acting as a lubricant and shock absorber to reduce pain and improve joint function.
Safety and Considerations
For most people, sodium hyaluronate is considered a safe ingredient for topical applications. It is generally well-tolerated by all skin types, including sensitive skin. This safety profile is a reason for its widespread use in the cosmetics industry.
When used in medical procedures, the context for safety shifts slightly. Injected forms, such as those for joint pain or as dermal fillers, must be administered by a qualified healthcare professional. The potential side effects are typically related to the injection process itself rather than the substance. These can include temporary redness, swelling, or bruising at the injection site, which are generally mild and resolve on their own.