If unidentified foreign objects have been swimming around in your makeup bag all winter long, now is the perfect time to roll up your sleeves for a deep spring cleaning that will leave your case -- and face -- looking refreshed and rejuvenated for the sunny season ahead.

Grungy makeup bags aren't just icky; they can harbor germs and bacteria that can actually make you sick or cause an eye infection. Too-old makeup can also lose pigment and texture, making shades turn muddy on complexions and crease, and possibly even aging your look beyond your years.

We've asked the experts for realistic advice on when you really need to chuck certain cosmetics, as we would hate to throw away perfectly good makeup for no reason -- but sometimes it's far past time to say goodbye.