Should you leave the toilet lid up or down when you flush?

For couples, families and anyone sharing a bathroom, the question of whether the toilet lid should be left up or down is often cause for heated debate. When looking at the spread of germs when you flush, the clinical answer is it’s better to close the toilet lid – but there are a few other things to know.

Like, do bacteria and viruses spread differently when flushed? And does it make a difference how the toilet is cleaned?

A recent study evaluated the virus spread when closing the toilet lid before flushing. While other studies show closing the lid reduces the spread of bacteria, scientists in this study wanted to see if this held true with viruses, as they are much smaller than bacteria.

The researchers infected toilet bowl water with a non-pathogenic virus, flushed the toilet with the lid either up or down, and then sampled various areas of the restroom, including the lid top and bottom, seat, walls and floor.

After analyzing the data, the researchers concluded closing the lid before flushing had no impact on the viral contamination of surfaces. Similar numbers of the virus were recovered from all surfaces tested no matter if the lid was open or closed when the toilet was flushed.

“While this study shows a closed toilet lid may not prevent all germs from contaminating bathroom surfaces, other studies show closing the lid reduces airborne particles by as much as 50% and may decrease the risk of contamination of harmful bacteria, such as Clostridium difficile,” says Dr. Brian Temple, who specializes in infectious disease at Aurora Health Care. “Anything you can do to help control the spray and spread of the toilet bowl water – like closing the lid before flushing – is worthwhile and recommended.”

The researchers also looked at the impact of toilet cleaning on viral contamination. Their results showed using a disinfectant and brush to clean the toilet bowl significantly reduced virus contamination of the toilet bowl water compared to cleaning with only a brush. Plus, the brush itself was significantly less contaminated when a disinfectant was used during cleaning. They also found adding disinfectant to the toilet bowl before flushing or using a disinfectant dispenser in the toilet tank reduced contamination.

“In general, and depending on how much it’s used, clean your toilet with a disinfectant once or twice a week,” Dr. Temple says. “But if someone in your household is sick, disinfect once or twice a day to help prevent others from getting sick. This includes the countertop, sink and faucet as well as the toilet. I also recommend always keeping your toothbrush as far away as possible from the toilet.”

Take another healthy step by scheduling an appointment with your provider. Find one in Illinois or Wisconsin.