Hyaluronic Acid Facial in Madrid.     What is the Hyaluronic Acid Facial in Madrid? Hyaluronic acid is a natural molecule produced by the human body. With age, hyaluronic acid reserves diminish. For example, at the age of 50 only 50% of the initial hyaluronic acid remains and as a consequence wrinkles appear and the skin becomes flaccid. At Full Leer más