This Is How Often You Should Be Washing Your Bedding (According To A Microbiologist)

*Sticks a wash on*

If you can’t remember the last time you washed your bed sheets, listen up.

A leading microbiologist in New York has urged people to wash their duvet covers, pillow cases et al once a week to avoid illness.

Philip Tierno, from New York University, told Business Insider that microscopic life can build up over time within bed clothes and, eventually, make people sick.

In fact, up to two weeks of buildup is enough to leave you with a scratchy throat, he said, especially if you suffer with allergies.

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The microbiologist said build-up of unwanted microbes and bacteria becomes “significant” in as little as a week.

Additionally, your unwashed bedding could also be making you sneeze and sniffle more as the microbes are near your face, meaning you’re likely to breathe them in.

Tierno said gravity plays a huge part in soiling your bedding: “Just like Rome over time was buried with the debris that falls from gravity, gravity is what brings all that material into your mattress.”

He isn’t the first to warn of the health implications of not keeping on top of your laundry. Mary Malone, a laundry expert at, previously said leaving bed sheets unchanged for long periods of time could lead to a whole host of health problems, such as infected wounds and athlete’s foot.

She said even when we sleep we continue to perspire, meaning body oils and soil are released.

“It is possible to find saliva, urine, genital fluids and faecal matter in the fibres,” she told ATTN.

“If the [sheets] are not washed regularly, and the occupant has scratches or wounds, they can become infected.”

She added that athlete’s foot and other fungi could be transferred from fabrics.

“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.

Professor Val Curtis, from the London School of Hygiene & Tropical Medicine, said she doesn’t believe leaving your sheets on for a few extra weeks can lead to health problems. That said, she advises people to change them once a week for “aesthetic reasons”.

Tierno concluded: “If you touched dog poo in the street, you’d want to wash your hands. 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?’”