We’re accustomed to washing our clothes whenever the hamper is full and we find ourselves with nothing to wear. We may wipe down the kitchen counter after washing the dishes that we’ll need to use again tomorrow. Most of us will run a duster over the surfaces in our home when visible dust starts to show up.

But at the end of a long day, it’s easy to fall into bed without giving your sheets a second thought. So how often should you be changing your sheets? Let’s take a closer look.

According to a 2012 poll by the National Sleep Foundation, 91 percent of people change their sheets every other week. Although this is a common rule of thumb, many experts recommend weekly washings.

This is because your sheets can accumulate a lot of stuff you can’t see: thousands of dead skin cells, dust mites, and even fecal matter (if you’re sleeping naked, which can be beneficial in other ways).

You should wash your sheets more often if:

  • you have allergies or asthma and are sensitive to dust
  • you have an infection or lesion that makes contact with your sheets or pillows
  • you sweat excessively
  • your pet sleeps in your bed
  • you eat in bed
  • you go to bed without showering
  • you sleep naked

Not washing your sheets regularly exposes you to the fungi, bacteria, pollen, and animal dander that are commonly found on sheets and other bedding. Other things found on sheets include bodily secretions, sweat, and skin cells.

This won’t necessarily make you sick. But in theory, it can. It could also trigger eczema in people with the condition or cause contact dermatitis.

People with asthma and allergies can trigger or worsen symptoms by sleeping on dirty sheets. More than 24 million Americans have allergies. But even if you’re not part of this group, you may experience a stuffy nose and sneezing after a night’s sleep if your sheets aren’t clean.

You can also transmit and contract infections through soiled linens, the results of a 2017 study suggested.

It’s recommended that you wash your sheets and other bedding in hot water.

Read the care instructions on the label and wash your sheets in the hottest setting recommended. The hotter the water, the more bacteria and allergens you remove.

Ironing your sheets after washing is also recommended.

You can keep your sheets clean between washing and help preserve them by:

  • showering before bed
  • avoiding naps after a sweaty gym session
  • removing makeup before you go to sleep
  • avoiding putting on lotions, creams, or oils right before bed
  • not eating or drinking in bed
  • keeping your pets off your sheets
  • removing debris and dirt from your feet or socks before climbing into bed

Other bedding, such as blankets and duvets, should be washed every week or two.

A 2005 study that assessed fungal contamination on bedding found that pillows, especially feather and synthetic-filled, are a primary source of fungi. The pillows tested ranged from 1.5 to 20 years old.

Pillows should be replaced every year or two. Using a pillow protector can help keep dust and bacteria to a minimum.

Duvets can last as long as 15 to 20 years when used with a cover and washed or dry cleaned regularly.

A little diligence when it comes to caring for your bedding can go a long way when it comes to helping you sleep — and breathe — easier. While it may seem like a hassle at times, changing your sheets weekly is well worth the effort.

If you’re accustomed to washing your sheets every other week, you may consider getting another set so you can swap them out without doing more frequent washings.

When you do wash your bed sheets, use the hottest temperature you can.

Use protective covers on pillows and follow the care instructions provided by the sheet manufacturer or on bedding tags.