In countries like Japan, China, Laos, Korea, Thaliand and Taiwan, removing shoes before entering the home is an absolute cultural must. In certain countries this custom extends to churches, temples, restaurants and schools as well. To leave the shoes on is to be rude and disrespectful to the homeowner and the home itself – something perceptually just as bad as putting your shoes up on the couch or table. But studies show this cultural trend just may have gotten its start from a very real phenomenon: outdoor shoes bring thousands of bacteria into the home.
High Bacteria Levels
To break down the facts, this study by the University of Arizona looked at 10 study participants from a variety of lifestyles who wore shoes outside and inside on a regular basis. They frequently tested and monitored the amount of bacteria found on the soles and inside sole of each shoe over the course of the study, identifying fecal coliforms and E. coli in almost every case.
Sky-High Bacterial Transfer Rates
Even more concerning is that researchers found evidence that the vast majority of that bacteria transferred into the home (e.g., onto the floor) after wearing them inside for only a short period of time. On average, scientists consistently demonstrated proof that around 99% of the 421,000 identified germs found on shoes successfully transferred to other surfaces.
That shouldn't be too surprising to anyone given the fact that public restroom floors have been found to contain around 2 million bacteria per square inch. Kelly Reynolds, Ph.D., a microbiologist and professor at the University of Arizona, put it into perspective when stating, "We walk through things like bird droppings, dog waste and germs on public restroom floors, all of which are sources for E coli." Then we track all that stuff into our own homes and transfer them to our floors, our carpets, etc. And that can easily transfer to our bare feet, our socks, and to our little ones who play on the floors.
Wash Those Shoes
Here’s the good news: you aren’t doomed to live with bacteria. Simple machine washing eliminated approximately 99% of all E. coli bacteria and up to 90% of all fecal coliforms found on the shoes. So, if you’re going to wear your shoes inside the house maybe it’s best to wash them frequently. Better yet, buy yourself a separate pair of comfortable shoes that you wear inside the house only, and leave the bacteria traps outside.
So taking our shoes off when we enter our own or someone else's home shouldn't be perceived as too much of an inconvenience anymore; it's just good manners and good hygiene.