One drawback of glossing compared to traditional color is that you'll need to repeat this treatment more frequently than dye, since it fades after a dozen or so washes (per MindBodyGreen). But that makes gloss the perfect solution if you've been thinking about changing up your hair hue but aren't quite ready to pull the trigger. You can also use a gloss on top of permanent hair color, to fine-tune the look — making it darker, deeper, redder, or brighter. "It's mixed specifically for a client and their needs," colorist Lucille Javier explained to Elle. 

Since a gloss is less expensive than conventional color, you also can use it in between dyes to save a little money on your upkeep. "I always recommend my clients come in for a gloss at the halfway mark between their color appointments just to keep things looking really fresh," hair stylist Lauren Miller told Oprah.