What is Hyaluronic Acid? Hyaluronic acid is a naturally occurring glycosaminoglycan, which means that it is a youth-supporting part of the skin. It keeps skin stable, extremely hydrated, and protected. Hyaluronic acid's extreme ability to retain moisture is exceptionally important as we age, as it significantly improves loss of firmness. What is the difference between Hyaluronic Acid and Sodium Hyaluronate? Sodium Hyaluronate is a salt derived from Hyaluronic Acid that contains all of the same benefits, but is more easily absorbed into the skin.