Mary added that by avoiding regular washing, dirty linen can infect other parts of the bed.
She continued: "Infrequent cleaning of sheets and pillowcases allows the fluids to seep into the pillows and mattresses, and those are much more difficult to clean than tossing sheets in the washer."
In order to avoid an unhygienic sleep Mary recommends that people wash and change their sheets once a week to keep them fresh.
But it seems that the public is reluctant to commit to regular washing as in 2014 it was revealed that one in ten people don't change their sheets more than once a month.
In a survey about household habits, 35 per cent of adults said they changed their bed linen once a fortnight.
Just over a third made sure to wash their sheets once a week.
And one in ten, identified in the poll as "au naturels", confessed they didn't bother to throw their linen in the washing machine more than once a month.
This is equivalent to five million adults nationwide. Asked by UK pollsters YouGov when they considered unwashed sheets to become unhygienic, half of those polled said between two and three weeks.
Change your duvet cover using the rolling method
1. Lie duvet cover inside out on bed
2. Place duvet on top and line up corners
3. Roll from the top down
4. Grab the bottom corners and turn the rolled up quilt inside out
5. Button up the fastening at the bottom
6. Separate the bottom from the roll and unravel towards the head of the bed