Here's how often you should clean and replace your pillows, according to allergists

If you're like most people, you probably find a pillow you like and stick with it until it basically disintegrates. But while having a comfy, lulling pillow is crucial to a good night's sleep, sticking with the same one for ages isn't the best thing for your health. And if you rarely — or never — wash your pillow, that's even worse. "Your pillows are filled with dust mites as well as other allergens that you bring into bed with you," Dr. Purvi Parikh, an allergist and immunologist with the Allergy & Asthma Network, tells Yahoo Life. If you're an allergy sufferer, you're doing yourself a huge disservice by not cleaning and replacing your pillows on a regular basis. So: How often should you wash and replace your pillows? The answer might surprise you.

In general, allergists say you should be washing your pillows at least once a month. "Pillows should be washed regularly in hot water," Dr. Shaan Waqar, an allergist and immunologist at ENT and Allergy Associates, tells Yahoo Life. "Once-a-month washing of your pillows can be very helpful to reduce dust mite allergen exposure." (Worth noting: It's important to read your pillow's label to make sure it's washing machine–safe.)

Got bad allergies? Consider washing your pillows even more often. "You should wash your pillows at least once every two weeks in hot water to kill germs, mold and dust mites that have colonized your pillows," Dr. Evan Li, an assistant professor of medicine in Immunology, Allergy & Rheumatology at Baylor College of Medicine, tells Yahoo Life.

You're probably aware on some level that using your pillow until it falls apart isn't a "best practice," but you're also likely not aware of just how often you swap it out. Well, the Asthma and Allergy Foundation of America recommends replacing pillows every two years to — you guessed it — protect yourself from dust mites and other allergens. That's true even if you're good about washing your pillow regularly. "They collect allergens, dirt and debris, even with frequent washing," Parikh explains.

Not sure how old your pillow is? There are a few hacks that can help signal when it's time to replace your pillows. One is the folding trick, which involves folding your pillow in half and putting a book on top of it. If the pillow is in good shape, it will open back up to its original shape; If it's not doing so hot, it will stay folded in half. (Memory foam pillows, by the way, should be replaced when they can't keep their original form.)

You can also help extend the life of your pillows — and keep dust mites from penetrating your pillow — with pillow protectors, Parikh says.

As for which type of pillow tends to last the longest, down pillows tend to have the best longevity, but they're hard to wash, more expensive and can cause allergy flares in some people.

Been a minute since you tossed your nightly headrest? Consider these machine-washable options.

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