If you’re engaged in a constant internal battle about whether to leave your shoes at the door to avoid tracking dirt and bacteria from the outdoors throughout your home or to keep them on in the name of comfort and style, a verdict is here—but it depends on how often you clean.

No matter whether you live in a city or a rural area, you’re probably stepping on things that you’d don’t particularly want hitching a ride into your Zen den. And if you use public restrooms frequently—whether at work or while shopping or really any other time—even more gross little microbes jump onboard. “Just because it looks physically clean doesn’t necessarily mean it’s sterile,” Meghan A. May, PhD, told Self. “When you walk on surfaces, you walk on microbes that wind up on your shoes. The opposite is also true: What’s on your shoes winds up rubbing off on the surfaces you walk on.”

“Just because it looks physically clean doesn’t necessarily mean it’s sterile.” —Meghan A. May, PhD

Now that it’s clear that all those teeny bacterial guys that cling to your shoes all day can easily end up scattered around you home, here’s the real question: Are they dangerous? The answer is that yes, they can be—but if you have a solid immune system and tidy up on the regular, you should be good to go. “If you’re young and healthy and you clean your house once a week, I think you’re going to be fine,” says Rachael Lee, MD. Having little kids around, on the other hand, changes things: Since they’re constantly hanging out on the floor, it’s possible that they could get an infection from something that came from the bottom of your shoes.

Ultimately, the decision is yours. You can leave your shoes at the door and not worry about what’s hanging out on your hardwood floors or wear them around and just make sure to keep things as clean as possible. Either way, it’s a best practice to tidy up your home sanctuary regularly to keep everyone safe and happy.

These are the germiest places in your home. Or, get some great all-natural cleaning-product recs to refresh your home.