How Often Should You Wash Your Bedding? Science-Backed Guidance

Most of us spend roughly a third of our lives tucked up in bed. Sleep is far more than idle time: it underpins healthy brain function and supports overall wellbeing. And although we often obsess over the number of hours we get, the condition of the space we sleep in also plays a part.

Slipping into a clean, inviting bed - with crisp sheets, soft pillowcases and freshly laundered blankets - isn’t only pleasant; it can help you rest more comfortably.

That raises the practical question: how often do bed linens actually need washing?

A YouGov survey from 2022 found that only 28% of people in Britain wash their sheets weekly. Many respondents said they leave it considerably longer, and some reported going eight weeks or more between washes.

So what does evidence-informed advice suggest?

Here’s what’s really going on in your bed night after night - and why laundering regularly is about more than simply looking tidy.

While we sleep, we constantly shed hundreds of thousands of skin cells, release oils from sebaceous glands and perspire as much as about 300 ml (even if you shower immediately before bed). Our skin is home to vast numbers of bacteria and fungi, and as we turn and shift, many of these microbes end up on sheets, pillows and duvets.

Fresh sweat might not have much of a smell at first, but skin bacteria - especially staphylococci - metabolise it into pungent compounds. That’s a common reason you can wake up with body odour despite going to bed clean.

Microbes aren’t the only issue. Throughout the day, our hair and bodies pick up pollutants, dust, pollen and other allergens, all of which can be carried into bedding. These irritants may set off allergies, interfere with breathing and worsen bedroom air quality.

Dust mites, fungi and other unseen bedfellows

The skin flakes you lose overnight provide a steady food source for dust mites - tiny organisms that do well in warm, humid bedding and mattresses. Dust mites themselves aren’t harmful, but their faecal pellets are powerful allergens that can exacerbate eczema, asthma and allergic rhinitis.

Beds can also support fungal growth. Certain species, including aspergillus fumigatus, have been identified in used pillows and may cause severe lung infections, particularly in people with compromised immune systems.

If you share your bed with pets, the microbial mix becomes even more intense. Animals bring additional hair, dander, dirt and, at times, traces of faecal matter into sheets and blankets, meaning they typically need washing more frequently.

So, how often should you wash your bedding?

Sheets and pillowcases

• When: Once a week - or every three to four days if you’ve been unwell, you sweat heavily, or pets sleep in your bed.
• Why: To clear away sweat, oils, microbes, allergens and dead skin cells.
• How: Wash at 60°C or above with detergent to kill bacteria and dust mites. For extra sanitisation, tumble-dry or iron. If you want to target dust mites inside pillows, freeze them for at least 8 hours.

Mattresses

• When: Vacuum at least weekly, and let the mattress air every few days.
• Why: Perspiration raises moisture levels, which helps create conditions in which mites can thrive.
• Tips: Fit a plastic or allergen-proof mattress protector, and replace the mattress every seven years to maintain hygiene and support.

Pillow interiors

• When: Every four to six months (check the care label first).
• Why: The inner filling can harbour bacteria and mould.
• How: Wash properly and ensure it dries completely to reduce the risk of fungal growth.

Blankets and duvet covers

• When: Every two weeks - and more often if pets lie on them.
• Why: They accumulate shed skin cells, sweat and allergens.
• How: Wash at 60°C, or as hot as the care label permits. Some guidance suggests treating these items like towels: frequent hot washes help keep them hygienic.

Duvets

• When: Every three to four months, depending on how they’re used and whether children or pets share your bed.
• Why: Even with a cover, body oils and mites can gradually work their way into the filling.
• How: Follow the care instructions: many duvets can go in the washing machine, while others need professional cleaning.

Your bed might appear spotless, yet it can quickly become full of microbes, allergens, mites and irritants. Washing bedding isn’t only about freshness - it’s also a health issue.

Consistent laundering strips out the biological mixture of sweat, skin, dust and microbes, helping to curb allergic flare-ups, reduce infection risk and prevent lingering odours. And as studies continue to underline how strongly sleep affects everything from cardiovascular health to mental sharpness, keeping your sleep space hygienic is a small but meaningful investment in your wellbeing.

So go on - change the bed. Get the sheets in the wash. Put the pillows in the freezer. Your microbes (and your sinuses) will thank you.

Sweet dreams - and happy laundering.

Primrose Freestone, Senior Lecturer in Clinical Microbiology, University of Leicester

This article is republished from The Conversation under a Creative Commons licence. Read the original article.