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Is it bad to share makeup?

Makeup and Hygiene

Using makeup in a hygienic way can help you avoid picking up an unpleasant disease. Many women get so involved in their routines that they may not even realize that what they're doing each morning is, in fact, putting them at risk of infection.

First, examine how you store your cosmetics. Make sure that you close your makeup containers tightly after using them each day. This helps keep the product in good, safe condition for a longer period of time. Cosmetics normally contain preservatives that help prevent bacteria growth, but storing products incorrectly can mean germs will be able to grow. An important aspect of this is keeping products at room temperature; storing them in a hot place or in direct sunlight will make it much easier for bacteria to thrive. Anything above 85 degrees Fahrenheit (29 degrees Celsius) becomes dangerous for makeup storage [source: FDA].

You should never add water to makeup, either, as this can spur germ growth in a previously clean environment and lessen the effects of any preservatives added to the makeup that keep it more sanitary. And using saliva is an even bigger makeup don't: It can spread bacteria from your mouth, where they are harmless, to your eyes, which are much more sensitive [sources: Connolly and FDA].

Now you know not to share makeup with friends -- but what about with strangers? Sounds obvious, right? Well, what do you think you're doing when you try the latest lipstick shade at your local department store's makeup counter? If you must use a tester or plan to have a makeover done by a department store makeup consultant, insist on disposable applicators, learn about cleaning procedures (make sure they follow them) and request a new tester product, if necessary [source: Wu].

Wondering what could be lurking on that lipstick tester? Read on to learn about the different infections that can be spread via makeup.