For starters, the average person changes his or her sheets every 24 days, according to a recent MattressAdvisor survey of 1,000 Americans.
Diving a little deeper in those demographics shows that single men are the worst perpetrators, changing their sheets every 45 days, or six and a half weeks.
Wondering about married folks? They change their sheets every 19.9 days.
The winners of the bedsheet-changing competition though are single women, who change their sheets every 19 days.
As for postcoital bedsheet changing, people might be lazier than you think, unfortunately. Single men wait 11 days before changing used sheets, while single women wait four days.
(Sorry, I know, ignorance can be bliss.)
These particular findings are ironic, since the survey also found that "not changing sheets immediately after a one-night stand" was considered the second-most "gross" sleep scenario by the respondents. (The first is wearing shoes while on or in the bed.)
So all of these findings beg the question: Is there valid hooplah to be made when it comes to washing our sheets, since no one seems to do it very often?
According to researchers, the answer is yes.
When sleeping, gravity draws our sweat, drool, hair, and skin cells into the sheets and ultimately our mattress and pillow, Philip Tierno, a microbiologist, told the New York Post. Dust mites love eating this stuff up, and in turn, they leave feces and parts of their little microscopic bodies all over our bed.
Now this isn't even counting those who eat in bed or have pets who climb over our beds, or the lotion and oils that come off our bodies and get all up in our sheets.
"The environment in that mattress becomes akin to a botanical park," Tierno said. "And what happens is, you kick up that material when you toss and turn in bed and you breathe in that material for eight hours or so at night and then you wake up with a stuffy nose or other issues.”
So we should be washing our sheets every week, or every two weeks at most. Our duvets, which have probably never left the top of our beds, should be washed every six months. Our pillows should be replaced every two years, and our mattresses, depending on their quality, should be replaced every 10 years or every 20 to 50 years.
As for the little dust mites, they don't really cause us that much harm, other than allergies, and those critters are also pretty much everywhere. If they really creep you out, consider an allergen-proof mattress cover, vacuuming your mattress, or flipping the mattress over every few months, according to Slate.
Source : http://thestir.cafemom.com/home_garden/210608/bed-sheets-how-often-wash