Karen - and This Morning viewers - were horrified when they saw the bucket of filthy brown water which had been sucked up from her bed
THIS Morning viewers ended up spitting out their breakfast after a woman who washes her sheets every four weeks learned what was lurking in her bed.
Brave Karen Aldridge, from Birmingham, let consumer expert Alice Beer into her home for a bed inspection.
But Karen - and This Morning viewers - couldn't believe what was lurking beneath the unwashed sheets.
Alice called in Luke Rutterford, an expert from Rentokil, to scour Karen's bedding, which she confessed hadn't been washed for four weeks.
A powerful vacuum cleaner was used to suck all the filth from her mattress, which Luke said was full of dead skin cells and bacteria.
He added: "One of the issues we have are dust mites. They are only tiny, between one to 1.5mm, and they can move down beneath the bedding and get into the mattress itself".
But before you get too smug about your own clean sheets, it's worth bearing in mind that everyone will be sharing their bedding with an army of mites.
However, the longer you go between washes, the more you're likely to attract.
Karen explained on the show that she had lived in her home for 27 years, and had been sleeping on her mattress, along with her husband, for three years.
But her son Joey had been sleeping on the same mattress for 12 years, with Alice admitting that she doesn't get to change the sheets as often as she'd like.
When asked how often she washes them, she said: "I would leave it three weeks, maybe four when things are hectic".
And the disgusting impacts of not washing your bedding often enough were highlighted earlier in the clip.
After Luke was done vacuuming her mattress, he revealed what the high-powered hoover has dredged up.
And Karen is predictably horrified when she sees the puddle of filthy brown water which has been sucked up from her bed.
She said: "That is just shocking, absolutely shocking. I can't believe how much dirt was in there".
But viewers weren't impressed with Karen's washing routine, taking to Twitter to slam her for only dealing with her sheets every four weeks.
If this has you concerned about your own dirty laundry, then you should listen up to hygiene expert Luke's advice.
He reckons you should vacuum your bed regularly, air out your mattress by opening the bedroom window and wash your sheets on a high temperature.
Last year, we told how an investigation revealed the shocking number of hotels which don't wash their bedding between guests.
And we've also previously revealed how often you should wash your sheets, according to medical experts.