A leading microbiologist from New York has advised people to wash their bed sheets once a week to avoid illness.
Philip Tierno from New York University told Business Insider that microscopic life can build up over time and within a week gunk becomes “significant”.
Tierno explained that not washing your bedding for two weeks will leave you with a build-up that can leave you with a scratch throat especially if you suffer from allergies.
Unwashed bedding can also make you sneeze and sniffle more as the microbes are near your face, meaning you are more susceptible to breathing them in.
"Even if you don't have allergies per se, you can have an allergic response," Tierno said.
In a recent study, researchers found that a test sample of feather and synthetic pillows that were more than 11.5 -20 years old contained up to 16 species of fungus each.
Mary Malone from about.com explained that leaving bedsheets unchanged can lead to health complications such as infected wounds and athlete’s foot.
“It is possible to find saliva, urine, genital fluids and faecal matter in the fibres,” she told ATTN.
“Infrequent cleaning of sheets and pillowcases allows the fluids to seep into the pillows and mattresses, and those are much more difficult to clean than tossing sheets in the washer,” she said.
As well as your own microbial life, you can also find pollen, soil, lint, dust mite debris and faeces and finishing agents in your bedding.
"If you touched dog poo in the street, you'd want to wash your hands," Tierno said. "Consider that analogous to your bedding. If you saw what was there — but of course you don't see it — after a while you have to say to yourself, 'Do I want to sleep in that?'"
How often do you wash your bedding? Let us know in the comments below.