Two thirds of us sleep in dirty night clothes – and poor quality sleep is the least gross of the downsides

You only wear your PJs after your evening shower or bath, so they don't need washing often, right? Wrong: according to the Clean Living Institute, nightwear ought to be washed after three or four wears, and the majority of us are putting ourselves at risk from bacteria (you'll know they're there when your nightie starts smelling), dust mites (bad news for allergy sufferers), and even bed bugs (ouch!) by not washing it often enough. The result? A poorer night's sleep.

A recent poll of 1,000 people reveals that only 32 per cent of us wash our clothes often enough, while 32.5 per cent wash our nightwear once a week. A further 35.5 per cent leave it unwashed for two weeks or longer, and 7.5 per cent leave it as long as a month before they pop their PJs in the wash. Really?

Somewhat surprisingly, women are more unhygienic than men, with only 7 per cent of women washing their nightwear after every wear, as opposed to 12 per cent of men. Under 25s have the worst track record for keeping their nightwear clean, with 42 per cent of people in that age group leaving it a month or longer to launder their pyjamas. 

If these stats are making your stomach turn a bit, they should (and they are ours). A human body sheds millions of skin cells every night (food for dust mites) and produces 200ml of sweat. Need we say more? 

• How to get rid of dust mites (other than washing your nightie)

Rebecca Brown from Pretty You London which conducted the poll, has plenty to say: 'Our research has exposed some shocking results about how dirty the nation’s nightwear is. Given the fact that we wear nightclothes for around seven to eight hours every night, and that our bodies expel night time sweat, it’s definitely an area where people should try to be more hygienic. 

'Some fabrics are better than others at withstanding night time dirt. Bamboo Viscose, for example, is anti-bacterial and has odour protection, limiting some of the health problems that have been associated with unclean nightwear. It is also hypoallergenic, meaning it is super sensitive and gentle against the skin. 

'In trying to extend the life of their nightwear, people are perhaps being too cautious when washing certain garments. Lots of nightwear is made from delicate fabrics with pretty embellishments, which means they look gorgeous, but it can put people off regular washing. Yet when washed with care, it’s easy to keep even the most delicate nightwear fresh and hygienic.'

Wondering how to wash your nightwear properly? Consult our guides on how to do laundry and how to handwash clothes (if you nightwear is of the silky, lacy variety).