A win for slippers

Scientists Have Entered Into The ‘No Shoes Inside’ Debate

Mend your socks, because researchers have found that wearing shoes inside can harm your indoor air quality.

Time to find a good place to pile outdoor shoes, because the experts say wearing shoes inside tracks...
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Growing up, I lived in a strict no-shoes-inside household. My dad is Korean, and it’s a common cultural thing in many Asian homes. On top of that, my parents were also both microbiologists — and they had a pretty good idea that tracking in a bunch of junk from outside wasn’t the best idea generally. Shoes didn’t cross the welcome mat, and inside slippers and flip-flops ruled in our home.

Now science has entered the shoes inside debate, and they’ve solidly chosen a side: leave your disgusting shoes at the door, for your health.

Specifically, a group of environmental chemists have been studying household filth for a decade, and all of their research points to kicking off your kicks at the door. Their program, DustSafe, analyses vacuum dust from households around the world and looks for contaminants — and they’ve figured out that a lot of harmful stuff can come tromping through the door on your sneaks.

What do your shoes bring into your home?

It seems obvious that shoes bring with them dirt and crud. But it’s more complicated than that. About one-third of the filth in your home comes in on your shoes, and that can include harmful bacteria and microorganisms, toxins from asphalt, heavy metals, and chemicals from lawn and garden sprays, the group explained to CNN.

While you can’t stop all of that crap from getting into your house, taking off your shoes helps.

How household dust can harm you and your family

Humans spend about 90% of their time inside. So when you hang out in your house, you’re breathing in the dust that floats around in that air, the researchers say. This consists of all sorts of stuff that naturally builds up in a house — like skin cells and pet dander — as well as stuff that’s brought inside, like residue from your shoes.

A list of not-so-great stuff that you might be breathing in inside include microplastics, antibiotoic-resistent genes, PFAs, and toxic metals. Many of these things can blow in the window, but a lot of it gets tromped in.

Get some house shoes

The DustSafe team concluded by saying that while there are upsides to taking off your shoes, there aren’t many big downsides. Socks and slippers are great — and if you need arch or ankle support, just have a pair of indoor shoes that you slip on when you take your outdoor shoes off.

And yes, while there are studies that confirm that a little dirt actually makes your immune system stronger, you can easily get that dirt exposure outside, not on your floors and carpets. It can be bad to have a completely sterile house, or to use too many strong cleaning products to keep out germs, but let’s be honest: that’s not the issue for 99% of parents.

Long story short: taking off your shoes at the door helps you control household dust, toxins, and germs. It’s also an easy way to keep your floors cleaner for longer. And in many cultures and households, it’s the polite thing to do.