Clinical Microbiologist Warns of Hidden Bedding Hazards

The Importance of Regular Bedding Washing

A microbiologist has provided guidance on how frequently you should wash your bedding. According to her, some items may require more attention than you might expect. Primrose Freestone, a Senior Lecturer in Clinical Microbiology at the University of Leicester, explained that we leave behind "hundreds of thousands of skin cells" each night. This process exposes our sheets to countless bacteria and fungi.

Her insights, shared in an article, emphasize the significance of regular laundry for bed linens. She noted that every night, as we sleep, we shed hundreds of thousands of skin cells, excrete oils from our sebaceous glands, and sweat up to half a pint of fluid—regardless of whether we have showered just before bed.

Bacteria and Fungi on Our Skin

Dr Freestone further explained that bacteria and fungi on our skin end up on our bedsheets and duvets throughout the night. "Our skin hosts millions of bacteria and fungi, many of which are transferred onto sheets, pillows and duvets as we move during the night," she said. "That fresh sweat may be odourless, but bacteria on our skin, particularly staphylococci, break it down into smelly byproducts. This is often why you wake up with body odour, even if you went to bed clean."

In addition, she highlighted how pollutants attach to our bodies and hair while outside, all of which find their way into our bedding. These can trigger allergies, affect breathing, and contribute to poor air quality in the bedroom.

Dust Mites and Allergies

The skin cells we shed nightly serve as food for microscopic creatures known as dust mites. These critters thrive in the moist, warm environment found within mattresses and bedding. "The mites themselves aren't dangerous, but their faecal droppings are potent allergens that can aggravate eczema, asthma and allergic rhinitis," she said. "Fungi also find your bed appealing. Some species, like aspergillus fumigatus, have been detected in used bed pillows and can cause serious lung infections, particularly in people with weakened immune systems."

How Often Should You Wash Your Bedding?

Primrose offered specific advice on when and how to clean different types of bedding:

Sheets and Pillowcases

Wash them every week, or every three to four days if you’ve been ill, sweat heavily, or share your bed with a pet.
This helps remove sweat, oils, microbes, allergens and dead skin cells.
Wash at 60°C or higher. Use detergent to kill bacteria and dust mites. For a deeper clean, tumble dry or iron.
To target dust mites inside pillows, you can freeze them for at least eight hours.

Mattresses

Hoover them at least every week and air the mattress every few days.
Sweat increases moisture levels, creating a breeding ground for mites.
Primrose recommends using a plastic or allergen-proof mattress protector. Replace the mattress every seven years to maintain hygiene and support.

Pillow Interiors

Wash them every four to six months. Check the label first.
Internal filling can have bacteria and mould.
Wash thoroughly and dry completely to avoid fungal growth.

Blankets and Duvet Covers

Wash them every two weeks. Do it more often if pets sleep on them.
Blankets and duvet covers trap skin cells, sweat and allergens.
Wash at 60°C or as high as the care label allows. Treat them like towels: regular and hot washes keep them clean.

Duvets

Wash them every three to four months, depending on circumstances.
Body oils and mites eventually seep into the filling, even with a cover.
Check the label. Many duvets are machine-washable, others may require professional cleaning.

The Health Benefits of Clean Bedding

Primrose concluded by emphasizing that your bed may look clean, but it's teeming with microbes, allergens, mites and irritants that build up quickly. Washing your bedding isn't just about keeping things fresh; it's a matter of health. Regular laundering removes the biological soup of sweat, skin, dust and microbes, which helps reduce allergic reactions, prevent infections and keep odours at bay. As research continues to show the profound effect of sleep on everything from heart health to mental clarity, a hygienic sleep environment is a small but powerful investment in your wellbeing.