The typical Brit has never washed their pillow, and a whopping 20 per cent of the nation is sleeping on an unwashed pillow that they’ve had for five or more years.

In fact, 41 per cent of the country is sleeping on a dirty pillow, the nationwide study by Silentnight’s Anti Allergy Collection reveals.

The nation’s pongy pillows are of special concern when the levels of bacteria and dust in the average bed are considered. Worryingly, 10 per cent of the weight of an unwashed pillow aged two years or more can be made up of dust mites and dead skin cells.

While most of these strains of mite are entirely harmless, some such as aspergillus fumigatus, can trigger many common allergies, causing hay fever-like symptoms, and even triggering some conditions such as eczema and asthma.

Silentnight’s Anti-Allergy Collection, which also has anti-bacterial properties to keep pillows cleaner for longer, surveyed 2,000 Brits about bedtime bad habits and found that, somewhat surprisingly, men are more likely to wash their pillows than women; 45 per cent of men have washed their pillows compared to 35 per cent of women.

Speaking on behalf of the Anti-Allergy collection, Sally Bonser said, “Many Brits consider themselves to be house proud and would baulk at the thought of having a dirty home – but as our results show, spring cleaning and good housekeeping is rarely extending to our bed linen.

“Quite unwittingly, many people will find that their bed is a magnet for bacteria and that this could be having quite an effect on their health. We’d recommend everyone gives their pillows and other bedding a good wash or, even better, invest in products that have anti-allergy and anti-bacterial properties in order to actively address these issues.”

Certified with a British Allergy Foundation stamp of approval, Silentnight’s collection of Anti-Allergy products is filled with anti-allergy, anti-bacterial hollow fibres that have been specially treated to actively fight bacteria and the formation of dust mites to leave bedding feeling fresh and clean.

This anti-bacterial protection is added during the manufacturing process and cleverly disrupts the cells of bacteria that come into contact with the products so that they cannot function, grow or multiply.

What’s more, this protection lasts for the useful life of each product within the collection.