Hyaluronic acid is a glycosaminoglycan component. Hyaluronic acid occurs naturally in the dermis. It is thought to play a critical role in healthy skin by controlling the physical and biochemical characteristics of epidermal cells. It also regulates general skin activity, such as water content, elasticity, and the distribution of nutrients. Its water-absorption abilities and large molecular structure allow the epidermis to achieve greater suppleness, proper plasticity, and turgor. Hyaluronic acid is a natural moisturizer with excellent water-binding capabilities. In a solution of 2 percent hyaluronic acid and 98 percent water, the hyaluronic acid holds the water so tightly that it appears to create a gel. However, it is a true liquid in that it can be diluted and will exhibit a liquid’s normal viscous flow properties. When applied to the skin, hyaluronic acid forms a viscoelastic film in a manner similar to the way it holds water in the intercellular matrix of dermal connective tissues. This performance and behavior suggests that hyaluronic acid makes an ideal moisturizer base, allowing for the delivery of other agents to the skin. Manufacturers claim that the use of hyaluronic acid in cosmetics results in the need for much lower levels of lubricants and emollients in a formulation, thereby providing an essentially greaseless product. Furthermore, its ability to retain water gives immediate smoothness to rough skin surfaces and significantly improves skin appearance. For the benefits of hyaluronic acid to be realized in a cosmetic, the product needs to be applied on a regular basis as it is broken down in skin within 24 to 48 hours of application. note, this is not the case with hyaluronic acid injections as the technology used is different.