When I see mold on bread or my milk has chunks I get it - it's time to toss them. But, my makeup going bad? I had no idea. Even though most makeup's today lack the "toss after this date" sticker, there comes a time when they still have to be tossed (yes, bacteria can form and harm our skin). So, how can we know when our favorite products have gone bad? And what can we do to increase their lifespan? Makeup artist Rea Ann Silva, designer of the revolutionary Beautyblender sponge, gives us the real deal about our favorite products and some tips and tricks for applying and caring for them.

Savvy Miss: Is there a general rule about when to throw out makeup products? 

Rea Ann Silva: If a product isn’t smelling good, if it’s not the same color it started out to be, or if it’s chunky and different than it was before, it’s time to get new makeup.

SM: Do makeup counter people tell us myths about when to toss makeup so we’ll come back to buy the product sooner than we have to?

Silva: The cosmetic companies they work for train them to say those things because these companies are liable for people that get sick or suffer from any damages; there are safety regulations put in place they must follow.

SM: What do we need to know about makeup brushes and keeping our products clean?

Silva: You should never let your makeup brush, finger or any other applicator go into the actual container. There’s bacteria that will grow and contaminate the makeup, which leads to breakdown. Makeup artists are taught to offload makeup onto a palette and then dip the applicator into it so that you’re not cross-contaminating the makeup. Secondly, you should absolutely clean your brushes as often as possible—every time you use them. If not, set a time once every couple of days or once a week to do so.