The active ingredient in the Filler family of products is hyaluronic acid. The flexibility, texture, and resilience of youthful skin exist because of the high amount of water it contains. Also known as hyaluronan, hyaluronic acid is a sticky substance that our body naturally produces. The skin, eyes, and connective tissue are the sites where maximum amounts of hyaluronic acid are found. Its capacity to retain water up to almost a thousand times its weight is the key reason why it is used in cosmetic fillers. Apart from hydration, hyaluronic acid is also linked to tissue repair, rejuvenation, and has anti-inflammatory action. Hyaluronic acid also facilitates new cell growth and promotes tightness and volume of the skin.