Hyaluronic acid is the water-binding fluid found in the joints. It is virtually unmatched in hydrating the skin because it retains water more effectively than any other natural substance. Occuring naturally in the dermis, hyaluronic acid allows the epidermis to achieve greater suppleness and proper plasticity. When applied topically, it forms a viscoelastic film, similar to the way it holds water in the intercellular matrix of the dermal connective tissues. HA combats facial wrinkles by enhancing the skin's smoothness, softness, and elasticity.