We’re so sorry to be the ones to share this gross information, but you’ll probably be glad we did. Here goes: After a couple of years of daily use, up to 30% of a pillow’s weight will be made up of dead skin cells, dust mites, and their feces, according to a study by a researcher at St. Bartholomew’s Hospital in London.
Dust mites that love to dine on dead skin can trigger breathing problems and asthma in people who are allergic to them.
Skin oils, saliva, and sweat also build up in the cover and filling of your pillow, bringing stains and odors with them.
No wonder allergists and cleaning experts recommend cleaning your pillows twice a year. Here’s how to do it.
Spot-treat stains on your pillow
Since you’re going to cover your pillow with a fresh, clean pillowcase at the end of this process, spot-cleaning is optional.
That said, if you want to get rid of dark blotches from perspiration, saliva, or blood, you can pre-treat the stain just as you would a stain on your clothes, says Donna Smallin Kuper, author of Clear the Clutter, Find Happiness. For fresh blood, flush with cold water to get as much of the stain out as you can before washing.
If the blood is dried, the American Cleaning Institute recommends using a stain remover with enzymes (like ones meant for pet stains). An enzyme cleaner will help with dried sweat and saliva, too or sponge with a sparing amount of white vinegar.
Machine- or hand-washing a pillow
Depending on the material, some pillows can be tossed into the washing machine, while others should be hand-washed, says Smallin Kuper. If you’re not sure, check the tag for specific care instructions.
Down and synthetic-filled pillows: “Synthetic and down pillows can be washed in a washing machine on the delicate cycle,” says Smallin Kuper.
Most delicate cycles default to cold or cool water, but you can use warm if your pillow needs a deeper clean, according to Martha Stewart.
Some cleaning experts recommend a detergent-boosting washing powder to properly clean a pillow, but Smallin Kuper says a gentle liquid detergent is just fine. “Don’t overdose, because you want to make sure all the suds come out,” she says.
Pillows are infamous for throwing washers off-balance, but she has a fix for that: “If you have a top loader, put two pillows in to keep the load balanced.
If you have a front loader, you can add a couple of bath towels to balance the load.” Run the pillows through a second rinse cycle to make sure all the soap is gone. This is especially smart advice for down pillows since soap residue can cause feathers to clump.
Memory or latex foam pillows: If you have a foam pillow, be double sure to check the care tags some manufacturers recommend against washing because wet foam can tear.
In that case, the experts at the Good Housekeeping Institute recommend dabbing any dirty spots with lightly soapy water, rinsing with a damp cloth, then air drying.
For washable foam, Smallin Kuper suggests soaking the pillows in a tub of warm water with a little detergent. “Squeeze the suds through the foam, then rinse, rinse, rinse and squeeze out excess water,” she says.
How to dry your pillow
Foam pillows can melt in a dryer, so always air-dry those. “Let them dry flat on a ventilated surface, preferably outside on a warm, sunny or breezy day to speed the drying process,” says Smallin Kuper.
Feather and synthetic pillows can generally be dried in the dryer on a low heat setting. “Add a couple of clean tennis balls to break up the filling and prevent clumping,” she says. Check the pillows after 30 minutes and every 15 minutes thereafter until they are completely dry.
Bonus tip for an extra-clean pillow
If you’re allergic to dust mites, you might want to give your pillows a little extra attention, says Smallin Kuper. “Placing them in the sun or running them through the dryer every month or so will kill dust mites,” she says.
How often you should replace your pillow
Just because you clean your pillow regularly doesn’t mean it’ll last forever. There’s no hard and fast rule on how often you should replace your pillow, but the National Sleep Foundation suggests swapping yours out for a new one every one to two years.