Jars
Anything that comes in pots or jars, be it your gel eyeliner, bronzer or eye cream, should never be exchanged with other people. We usually use our fingers to apply these products on our faces and it is the fastest way germs can travel and eventually be absorbed by our skin, especially when it comes to super absorbent skin care products.
Mascara
You probably know this already, but sharing mascaras is very unhygienic. Here's why: Since mascara feathers attract bacteria when they come in contact with our lashes and then those germs are pushed back into the bottle, makeup pros often swear by disposable wands. That means you can never borrow mascara even for finishing touches.

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