Wearing your shoes inside the house is apparently much more dangerous than you thought, as it is a way to spread harmful bacteria that causes sickness, as found by researchers from the University of Houston.

The paper explains that the bacteria brought indoor can multiply and make you prone to stomach problems like diarrhea.

Professor Kevin Garey, the study co-author, explains:

“It’s amazing how far humans travel during the day. And all that walking drags in germs and bugs.”

The team analyzed 2,500 samples and found that a quarter of shoe soles tested positive for a bug that causes painful stomach cramps.

Researchers actually showed that bacteria thrive better on shoes than toilets. Namely, a study conducted at the University of Arizona studied bacteria on shoes and found that 440,000 units of bacteria attached themselves to the soles within two weeks. Researchers also found that when one walked over clean floors, bacteria did contaminate the floors more than 90 percent of the time.

According to Dr. Charles Gerba, professor of microbiology and environmental sciences at the University of Arizona, who studied the bacteria on the bottom of shoes:

“If you wear shoes for more than a month, 93 percent will have fecal bacteria on the bottom of them. We found E. coli, too. The common occurrence (96 percent) of coliform and E. coli bacteria on the outside of the shoes indicates frequent contact with fecal material, which most likely originates from floors in public restrooms or contact with animal fecal material outdoors.

Our study also indicated that bacteria can be tracked by shoes over a long distance into your home or personal space after the shoes were contaminated with bacteria.”

According to CDC, even though these bacteria are usually not harmful, some strains can make you sick, cause pneumonia and respiratory illness, diarrhea or urinary tract infections.

He said:

“Shoes make microorganisms fairly mobile, and you’re tracking that all around (the house). Also, if you’re immunocompromised or have allergy issues, it’s a good idea to take your shoes off, as shoes also pick up mold and allergens like pollen.”

Also, chemicals used in farming or toxins used on the lawn can also end up on your shoes. A 2013 study conducted at the Baylor University found that people who live near asphalt roads sealed with coal tar had a higher risk of cancer from toxins brought in the home by their shoes.

The habit of not leaving the shoes outside will also ruin the floors over time, wear down the carpets, carry toxins inside that pollute the air, and track in dirt.  So, it will only take you a second. Take your shoes off before going inside, and you will avoid all these possible risks altogether. 

Sources:
www.huffingtonpost.com
www.medicaldaily.com