From lipstick to mascara, find out exactly when you should be replacing your favorite cosmetic items.

Mascara
Toss it: Every 3 months
The reason: In order to prevent an eye infection (bacteria love to hide away in these pretty tubes), replace your mascara four times a year. Plus, by three months your mascara will likely be dried up and cakey anyway. When you're applying mascara pumping the tube can cause it to dry out faster, instead twirl the brush inside to decrease the amount of air that gets in.
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Eyeshadow
The reason: Just like powder blushes and bronzers, powder eyeshadows can last up to two years. But if you apply it every day, beware that bacteria build up could result in an eye infection (not a good look), so be sure to keep brushes clean. If you're using a cream-based eyeshadow toss it after one year.
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Eyeliner
The reason: Gel and liquid liners that are applied with a brush should be tossed every six months to avoid an eye infection. Eye pencils and retractable pens have a longer shelf life since they're constantly getting sharpened or worn down. Just in case you don't use them up in a year, they should meet the trash can after the first anniversary.
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Foundation
The reason: Avoid applying liquid foundation with your fingers as that can cause bacteria to build up quicker; brushes and sponges, when washed regularly, can help your liquid foundations last a year. If you use foundation out of a squeeze tube or bottle with a pump, application style doesn't matter as much. Store in a cool, dry place away from direct sunlight and close the lid tightly to keep it from bacteria and drying out. In general, color and consistency will turn after a year.
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Concealer
The reason: If you have concealer in a pan (like the one pictured), it can last up to 18 months if you apply it wth a regularly-washed brush or sponge. If you apply with your fingers, though, you're more likely to transfer bacteria. If you have concealer in a tube with a wand you'll only want to keep it in your makeup bag for a year before it starts to turn.
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Blush & Bronzer
The reason: Powders, since they don't contain oils and water, have a longer shelf life than most other cosmetics. As a rule of thumb, toss these when the color darkens or starts to cake up. And while these products aren't as succeptible to bacteria build up, be sure to wash your brushes frequently (try this DIY brush cleaner) to keep them clean.
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Lipstick
The reason: The perservatives in lipstick can break down after a year. if you're not sure when you bought your favorite tubes, chances are good it's time to toss them if the surface gets hard or small beads start to form on the bullet. Tip: If you're under the weather, apply lipstick with a fresh cotton swab to stop it from becoming contaminated.
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Lip Gloss
The reason: Lip gloss in a tube with a wand applicator should bite the dust after 6 months due to bacteria build up. But the good news if you have lip gloss in a squeeze tube is that you can hold on to those for closer to a year since bacteria has a much smaller chances of getting in the product.
Photo Credit: Getty Images/Paul Tearle

Makeup Brushes
The reason: Brushes can have a varied lifetime depending on how high quality they are and how often you wash them. Quality brushes that you maintain really well can last for years! You should wash your brushes every day if you use them every day (but if it's once a week you're probably ok!). Here's a good DIY brush cleaner, but we've also found that Johnson's baby shampoo works well too thanks to its gentle formula. Clean brushes will help your other makeup products last longer as well, and your makeup will look better when applied with well-kept tools.
Photo Credit: Getty Images/Steve Wisbauer

Makeup Sponges
The reason: If you're really dilligent about cleaing your makeup sponges, then they can last up to a month. And even then they need to be washed after every use. Otherwise you should toss them after every application. Luckily, makeup sponges are pretty inexpensive at most drugstores.
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Nail Polish
The reason: The chemicals in nail polish will start to degrade after one year. Plus after a year the color may start to yellow and the polish has probably dried out and become thick and harder to apply after this amount of time. If you're nervous that you won't fnd your favorite color again, stock up on a few bottles and only open a new one when it's time to toss the old one.
Photo Credit: Getty Images/Steve Wisbauer