One of the first things we learn as kids is that it’s important to wash our hands.
Handwashing helps prevent disease spread. It can keep an office running instead of shutting it down due to a viral illness.
It’s especially important to wash your hands if you are interacting with newborn children or potentially vulnerable elderly adults.
But we don’t always appreciate the reason why handwashing is so important: we touch a shocking number of filthy surfaces every single day.
Here are some of the most surprisingly dirty things we come into contact with on a regular basis.
Most of us touch our phones dozens of times a day, at minimum, reaching for them at just about any quiet moment. But aside from the occasional T-shirt swipe, we rarely clean these devices.
That’s unfortunate, according to Philip Tierno, a microbiologist and pathologist at the New York University School of Medicine.
It’s common to find bacteria and viruses from skin, your respiratory tract, and from fecal matter on cell phones. Some of the pathogens found include E. coli, MRSA, and Streptococcus.
“If you’re not cleaning your phone, you should,” Tierno told Business Insider. A microfiber cloth will remove most (though not all) bacteria. There are other recommended cleaning products that can get the job done too.
The kitchen sponge:
It turns out that the thing you use to wash your dishes is teeming with bacteria.
In fact, many microbiologists identify it as the dirtiest single item in your household (far, far dirtier than your toilet seat).
Sponges, which are often warm, wet, and have traces of food on them, are ideal breeding grounds for bacteria. One NSF (formerly, the National Sanitation Foundation) study found that more than 75% of sponges were contaminated with coliform bacteria, which indicates fecal contamination and from the same family as Salmonella and E. coli. Campylobacter, the biggest cause of foodborne illness in the US, is also commonly found on sponges.
Tierno recommends using bleach to clean your sponge.
That dish towel you just used to dry your hands:
Knowing that your sponge is dirty, you might be inclined to wash your hands after doing the dishes. That’s wise!
But unfortunately, reaching to grab the dish towel that you keep by the sink might undo some of the good you did by washing your hands in the first place. Dish towels frequently have the same issues as sponges, since they’re also damp, warm, and come into contact with food particles.
One study found E coli. on more than 25% of dish towels, putting them firmly into competition with sponges. Wash them after two days of use.
That cozy bed:
The fact that your kitchen and phone are so dirty might make you want to bury your face into your bedsheets. But when did you wash them last?
Beds share many of the same characteristics that bacteria love. Humans sweat a lot, so they’re wet and warm — ideal for bacteria and for fungal growth. And our skin particles rub off onto our sheets along with everything we’ve come into contact with during the day.
The result is enough to make a germaphobe wince. Wash your sheets once a week or so, say experts.