And a similar percentage of people has owned a pair of knickers or underpants for more than 10 years.

The survey showed 5% of the population also admitted wearing their briefs inside out to get an extra day's wear.

Carried out by soap company Surcare its results were studied by Gaynor Lea-Greenwood, a fashion lecturer at Manchester Metropolitan University.

"We clearly have a lot to learn in the pants' department," said Ms Lea-Greenwood, senior lecturer in fashion marketing.

"It appears we have some curious ideas when it comes to cleanliness."

And more than half of the population have 10 to 20 knickers or pants in their underwear drawer.

The survey also revealed sharp regional variations such as 34% of people in the West Midlands spray their undergarments with perfume to make them smell better.

This compares with 17% of people in the South West and 19% of people in the North East.