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Is it bad to share makeup?

Avoiding Makeup Contamination

Open up that bathroom drawer, and you may discover makeup that is well beyond its normal usage date. However, the U.S. Food and Drug Administration, which oversees cosmetics, does not require that manufacturers set an expiration date for such products. On top of that, some types of makeup can expire faster than normal if they are stored incorrectly. That means that it's up to you to decide when it's time to toss your beauty products.

Since eyes are one of the areas of the body that are most susceptible to disease, you should be especially careful when keeping track of how long you've had your current mascara. The closed container creates a dark environment that allows germs to thrive. Most manufacturers suggest tossing mascara just after the three-month mark. Of course, if it smells odd, has become dried out or has been exposed to drastic temperature changes, you might want to chuck it sooner than that. And if you've had a recent eye infection, no matter how long (or little) you've had it -- you should replace all of your eye makeup [source: FDA].

Other liquid products, or those that contain a large amount of water, also are breeding grounds for bacteria and should be replaced on a regular basis. After six months, get rid of liquid foundation, creamy-formula eye shadow and blush. And, like mascara, after three months, discard liquid eyeliner [source: Matlin].

Powder-based products, which contain little water, can last for up to two years. These include pencil eyeliner and lip liner, and powder eye shadow, foundation, blush and bronzer. But this doesn't mean that every type of makeup will necessarily last this long. If a cosmetic changes color or starts to smell, throw it out right away.

To learn more about the dangers of poor makeup hygiene, visit the links on the following page.