Sodium hyaluronate is the sodium salt of hyaluronic acid. Hyaluronic acid is found naturally in the fluid that bathes joints, in the vitreous humor of the eye and in the skin. It's abundant in the dermis of young skin, but levels of this important compound decline with age. This makes skin look older. Hyaluronic acid gives skin volume by holding onto water and as levels decline with age, skin loses its youthful fullness. As an anti-aging treatment, dermatologists inject it into the dermis of the skin to restore facial fullness in areas where volume is lost. Sodium hyluronate is the main ingredient in Restylane, an injectable filler used to treat loss of facial volume and wrinkles. It has other medical applications as well. Doctors sometimes use injections of sodium hyaluronate to treat knee pain due to arthritis. In this setting, it helps to lubricate the joint and reduce pain and inflammation. It also has various applications in the field of ophthalmology.
Hyaluronic acid doesn't easily penetrate the skin when it's applied topically, so it is most successful when injected into the dermis of the skin through fillers like Restylane. This is due to its large size. Sodium hyaluronate is smaller than hyaluronic acid and is able to move more freely into the deeper layers of the skin. This is an advantage since sodium hyaluronate is a powerful humectant that attracts and holds on to water, making it the ultimate skin moisturizer. This helps to hydrate skin and keep it moist and supple. Because it attracts and binds to water, it causes slight swelling. This swelling helps to reduce the appearance of fine lines and wrinkles and gives skin a more youthful appearance. In addition, the subtle swelling increases volume, which makes skin look younger.
Not surprisingly, sodium hyaluronate has become popular with manufacturers of cosmetics and anti-aging skin care products. Its ability to penetrate skin and hold onto water makes it a popular ingredient in moisturizers, eye creams, facial cleansers, skin repair creams and other anti-aging skin care products. The fact that hyaluronic acid is found naturally in the dermis of the skin makes it even more appealing as a skin care ingredient. People are increasingly looking for products that contain natural ingredients that aren't toxic and won't harm or irritate skin. Sodium hyaluronate fits the bill. The Environmental Working Group's Skin Deep database classifies it as an ingredient with a low potential for toxicity and gives it a high safety rating.
Sodium hyaluronate is also not known to be irritating to skin, although people who get filler injections with hyaluronic acid in the form of Restylane may experience some localized irritation after the procedure. Unlike some moisturizing products, moisturizers and cleansers that contain sodium hyaluronate don't leave a "greasy" feel to the skin. This makes sodium hyaluronate beneficial as a moisturizer for most skin types. In moisturizers, it may be combined with other hydrating ingredients that form a protective layer on the surface of the skin, further increasing skin's ability to hold onto water. Since hyaluronic acid is naturally found in the dermis of the skin, products that contain sodium hyaluronate help to replace hyaluronic acid lost as a result of the natural skin aging process and sun exposure.
All in all, sodium hyaluronate is a safe and effective moisturizer and has the ability to bind and hold onto significant amounts of water. It has an advantage over hyaluronic acid, a molecule that has to be injected into the dermis due to its large size. Plus, not everyone is comfortable with having a needle placed into the skin on their face or the risks of injecting too much and not getting a good cosmetic result. Sodium hyaluronate has moisturizing benefits when applied topically to skin tissue. No injections are required. In addition, it mimics hyaluronic acid produced naturally by the body. It's non-irritating to skin and is usually well tolerated even by people with sensitive skin.