The word “filler” usually doesn't have the most positive of connotations: Filler conversations are boring; filler relationships suck; and filler anything is usually just something to pass the time until a better option comes along. Fillers in regards to your face, however, are a different story. They can enhance and improve, taking years off your appearance. To find out exactly how fillers work and what the appropriate age is to consider them, we spoke with Beverly Hills-based plastic surgeon Dr. John Diaz, and asked him all our pressing questions. Keep scrolling to learn everything you need to know about fillers!