New York University microbiologist, Philip Tierno, says leaving your sheets too long in between washes can turn them into a "botanical park of bacteria”.
Speaking to Business Insider, Tierno recommends washing your sheets once a week.
The publication explains: “Humans naturally produce roughly 26 gallons of sweat in bed every year. When it’s hot and humid outside, this moisture becomes what scientists call an “ideal fungal culture medium".
Just because you can’t see what bacteria and fungus are lurking in your bed doesn’t mean it’s not there.
"If you touched dog poo in the street, you'd want to wash your hands," Tierno said. "Consider that analogous to your bedding. If you saw what was there — but of course you don't see it — after a while, you have to say to yourself, 'Do I want to sleep in that?'"
This article originally appeared on Better Homes and Gardens.