Glycerin and Hyaluronic Acid are humectants that attract and hold water. However, they behave differently on the skin. Glycerin is a small molecule which is capable of absorbing at the skin’s surface. Hyaluronic Acid is a very large molecule that sits on top of the skin when applied, creating a hydrating cushion. Combining both Glycerin and Hyaluronic Acid provides a superior capacity for binding water and boosting hydration.