It may be common sense, but we all need the reminder -- flush the toilet with the lid down, lest you send a spray of diarrhea-causing bacteria up into the air, according to a new study.

The study, published in the Journal of Hospital Infection, shows that the bacteria Clostridium difficile, which is known to cause diarrhea, is sprayed 25 centimeters, or nearly 10 inches, above the toilet seat when you flush without putting the lid down, ABC News reported. The most bacteria was found right after the toilet was flushed, with the number of bacteria declining as time passed on.

"Almost everywhere we go, except in some public spaces, we have lids on our commodes. But not everyone puts them down when they flush," Dr. William Schaffner, chair of preventive medicine at Vanderbilt University Medical Center, told ABC News. "Doing so will reduce this type of environmental contamination very substantially."

Researchers from Leeds General Infirmary examined the airborne suspension of C. difficile bacteria in hospital toilets after they had been flushed, as well as which surfaces were contaminated with the bacteria after flushing, Medscape reported.

The researchers found that bacteria was 12 times higher after lidless toilets had been flushed, compared with when toilets were flushed with the lid down, according to Medscape.

Recently, germ expert Dr. Charles Gerba of the University of Arizona found that toilet paper and paper towel dispensers are also covered with bacteria, with the toilet paper dispenser containing more than 150 times and the paper towel dispenser containing more than 50 times the amount of bacteria found on a typical toilet seat.

And another study, conducted by University of Colorado in Boulder researchers, showed that gut bacteria aren't just found on the usual suspects (toilet seat or flush handle) -- they're also found on the stall doors, soap dispensers and even the bathroom exit handles, the Canadian Press reported.