Over time, foundations can change color or start to separate, two easy-to-catch expiration warning signs that Purdue says to keep an eye out for. She also notes that you're going to want to take special care with any foundations that don't come with a pump, as your fingers can contaminate the product, causing it to go bad faster.
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Sadly, lip glosses don't exactly last as long as you'd hope, which means you should probably toss that limited edition MAC Lip Glass you've been hoarding since high school. "I would throw out a lip gloss before a lipstick because you are pumping air and bacteria back into the lip gloss with the wand," explains Stoj.
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As for cream products, they can last up to around two years, especially if you keep whatever tools you use to dip into them (brushes, puffs, makeup sponges, etc.) clean. Also, it happens to be pretty easy to tell when to get rid of them: They can start to smell a little, well, rancid. "If a cream product's smell changes, it's time to throw it out," says Stoj.
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Lipsticks and lip liners tend to last a long time, though it's important to do your best to keep track. Anyone who's accidentally tried on a lipstick they found in their medicine cabinet from five years ago knows that the delicate skin on your lips can be pretty prone to irritation.
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Luckily, powder products have a relatively long shelf life, so you have some time before you have to throw out that luxe Tom Ford blush or your coveted Anastasia Beverly Hills Modern Romance Eyeshadow Palette.
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