How Often Should You Wash Your Sheets? Here’s What Germ Experts Recommend
Your sheets accumulate sweat, dirt, dust, and more: How much—and how often your dirty sheets need cleaning— depends on your skin, your habits, and your pets.
The importance of changing your sheets
Timing is everything, especially when it comes to cleaning, germs, and your health.
Think about it: you need to regularly replace your toothbrush and sponge. And there’s only so long you can go before it’s time to wash your hair. It’s equally as important to know how often you should wash your sheets.
Admittedly, stripping a bed, washing sheets, and then redressing it is a slog. But seeing as you spend lots of time in bed each week, you want to make sure you’re slipping between clean sheets.
Which begs the question: how many days can you go before it’s sheet-washing time?
We spoke with a dermatologist and a germ expert to get to the bottom of this question and explain the worst-case scenarios. And we’ll fill you in on who needs to wash their sheets more often than others.
How often should you wash your sheets—and why?
Most people should wash their sheets once per week, according to Annie Gonzalez, MD, a board-certified dermatologist at Riverchase Dermatology in Miami.
“The once-a-week wash can eliminate accumulated dead skin cells, fecal matter, dust mites, body oils, dirt, and sweat,” she says.
Philip Tierno, PhD, a germ expert and a microbiologist at NYU Grossman School of Medicine, agrees weekly sheet-washing is a good idea. That said, he notes that it depends on whether or not you have a mattress cover.
“You have to realize there is a difference between washing sheets that are covering a mattress and washing sheets that cover a mattress cover,” Tierno says. “So when you put a fitted sheet over a mattress without a barrier, you still have the ability of those fibers and particles and odorous material coming through that fitted sheet.”
Over time, mattresses accumulate debris like human skin cells, dust, dust mites, sweat, and even animal hair and pet dander. They also collect residue and oils from lotions, and food particles if you eat in bed.
That’s why Tierno highly recommends mattress covers. The extra barrier may mean you can wash your sheets biweekly, depending on how often you bathe.
Although there is a lot of material that can find its way between your covers and sheets, remember that it’s important to protect yourself from (and avoid adding to) what accumulates in your mattress.
Who should wash their sheets more often?
If you don’t have a barrier or mattress protector, debris comes into contact with your sheets and, ultimately, your body. It even goes into the air you breathe.
And if you have skin issues such as eczema or acne, drool on your pillowcase often, sleep with pets, don’t shower before bed, and sleep naked, Dr. Gonzalez recommends washing your sheets at least twice per week.
Those who eat in bed, sweat excessively, or have asthma or allergies should also wash more frequently.
“Drool on your pillow can cause acne,” she says. “Not showering before bed allows for dead skin cells to accumulate on your sheets. And your dog can track fecal matter on your sheets.”
Dirty sheets can irritate sensitive skin and may make asthma and allergies worse. What happens if you don’t wash your sheets?
You know you need to wash your sheets, but you have better things to do. Like sleep. Here’s what can happen if you don’t regularly change your sheets.
So what’s the worst-case scenario if you don’t wash your sheets often enough? Oil, bacteria, dead skin, and dirt can block your pores and contribute to acne, according to Dr. Gonzaalez.
Not washing your sheets may cause contact dermatitis (a red, itchy rash), trigger eczema, and exacerbate already existing acne. (That’s just one way your messy house is making you sick.)
In addition, the friction from dirty sheets rubbing against your skin can lead to skin irritation. Rashes or infections, such as tinea versicolor, a common fungal
infection that causes discolored patches of skin, can also transfer to your skin from dirty sheets.
If you sleep naked, a buildup of fecal matter can end up on your sheets, and your eyes and mouth can be exposed to this dried fecal matter, according to Dr. Gonzalez.
Tierno notes that a lot of material can find its way in between those sheets and contribute to odor.
Another scenario to consider: Imagine sleeping in someone else’s sheets that aren’t clean.
“Let’s say you’re sleeping with somebody who has a [staph] strain that your body is not accustomed to,” Tierno says. “If you have a [cut], sometimes even without, you could develop an infection.”
It’s possible because you’re in an environment riddled with cells and microorganisms.
In addition to odor, the accumulation of particles could challenge your respiratory system with particulars that you’re inhaling, according to Tierno.
Remember, you spend about eight hours—or one-third of your life—inhaling whatever debris is in your mattress, pillows, and sheets, Tierno says. So if you don’t wash them, you’re inhaling several weeks or months’ worth of accumulation.
And even if you don’t have allergies or asthma, constantly challenging your immune system over time may cause you to develop them, according to Tierno.
You can get allergic reactions by constantly inhaling dust particles that contain those materials, he says.
“In reality, it’s not that you may get an infection with these organisms, but they may exacerbate allergies and asthma if you have preexisting asthma,” Tierno says. “Or over time, you may develop asthma or an allergic reaction if you constantly breathe in large quantities of these particles.”
Advice for washing your sheets
“I recommend washing your sheets with the hottest water temperature since hot water kills most dust mites and germs,” Dr. Gonzalez says.
Cotton sheets can tolerate hot water, while it’s best to wash polyester sheets in warm water. You should also never cram multiple sheets into the washer. Sheets need to circulate to get clean, according to Dr. Gonzalez.
Tierno’s top piece of advice is to invest in mattress and pillow covers.
“Every single mattress and pillow that is in my home [have] mattress and pillow protectors,” he says.