Every week, you likely spend anywhere from 49 to 63 hours on your sheets. That leaves a lot of time for sweat, oil, dirt, and maybe even makeup to build up, possibly leading to skin issues like breakouts, more allergy symptoms, and even conditions like fungal infections.
That's why it's so important to keep your sheets clean. But just how often should you wash them? Running your sheets through the washer too often can break down the fabrics and cause them to wear out faster. On the other hand, washing them too rarely can let all that dirt and all those allergens like dust mites build up.
There isn't a hard-and-fast rule for how often to wash your sheets, but a good rule of thumb is to do it once a week. You can stretch that out to every two weeks, if you like, but you'll want to do it more often if you sweat while you sleep. And if you've been sick, toss them in the washer immediately to kill any lingering germs.
If washing all your sheets once a week just isn't doable, try to at least wash your pillowcases once a week, perhaps by tossing them into the washing machine with another load of laundry, because your face is more likely to break out than other areas of your body and you can ingest dust mites through your nose and mouth.
When you do wash your sheets, use warm water (hot water can shrink the fibers in the fabric) and tumble dry (never store sheets that aren't completely dry—it can lead to mildew).
Also, don't think that every single thing on your bed needs to get washed this often—duvet covers need to get washed just once a month, while pillows, comforters, and blankets need to get washed only a few times a year. When you do wash those items, use the delicate cycle and do an extra rinse cycle to make sure all the soap gets out.