Your Apple Watch or Fitbit may be a breeding ground for E. coli and staph bacteria. Here’s how to clean your fitness tracker

Your Apple Watch or Fitbit may be a breeding ground for E. coli and staph bacteria. Here’s how to clean your fitness tracker

Your fitness tracker might be carrying a dirty little secret, and it’s not how many steps you take.

Many TikTok users have taken to the platform to share that they’ve developed rashes from wearing their smartwatches. Some discovered they had contact dermatitis, which can be uncomfortable but will likely clear up in a couple of weeks. Others, had more potentially harmful infections.

Experts say it’s not surprising that our Apple Watches, Fitbits, Garmins, and other activity trackers can cause skin irritation and infection, as we wear them while working out, showering, sleeping, and during other every day tasks and likely don’t clean them as often as we should.

Family medicine doctor Mike Varshavski, DO, known as Dr. Mike on social media, posted a TikTok in 2022—that’s been viewed more than 5.7 million times—about the importance of taking off your fitness tracker and letting your skin breathe to prevent irritation and infection.

@doctormike Apple Watch Wearers Beware ⌚️#apple #applewatch #skincare ♬ original sound – Doctor Mike

How dirty are fitness trackers?

A 2023 study published in the journal Advances in Infectious Diseases examined 20 different smartwatch and fitness tracker bands and found that 95% were contaminated with infection–causing bacteria.

Researchers found that 85% of the trackers tested had Staphylococcus aureus (Staph aureus), 60% had E. coli, and 30% had P. aeruginosa bacteria present. Simply put, they were carrying bacteria that can cause harmful infections in the bloodstream, bones, joints, and GI tract. 

“Even at relatively low numbers these pathogens are of public health significance,” said Nwadiuto Esiobu, PhD., senior author and a professor of biological sciences in the Charles E. Schmidt College of Science at Florida Atlantic University, in a press release about the study.

“The quantity and taxonomy of bacteria we found on the wristbands show that there is a need for regular sanitation of these surfaces.”

The researchers tested plastic, rubber, cloth, leather, and metal wristbands to see the correlation between the material and the amount of bacteria present. Bacteria tended to cling to rubber and plastic bands the most, with little to no bacteria present on bands made of gold or silver, according to the study.

How to help prevent infections from fitness trackers

You can reduce your exposure to bacteria with simple cleaning measures. 

Clean the band with common household disinfectants regularly

The study found that Lysol disinfectant spray, 70% ethyl alcohol, and apple cider vinegar proved to be at least somewhat effective on all fitness tracker band materials.

Lysol and ethanol killed 99.99% of E. coli, Staph aureus and P. aeruginosa after 30 seconds of contact on most bands, though needed two minutes of contact for plastic bands. However, apple cider vinegar wasn’t effective on Staph aureus, even after five minutes.

It is important to note that for the bacteria identified, the recommended usage time for Lysol Disinfectant Spray is five minutes, where the Centers for Disease Control and Prevention finds that 70% ethanol is effective against P. aeruginosa, E. coli, and S. aureus after 10 seconds. 

Follow the manufacturer’s instructions for cleaning the hardware

Companies like Garmin, Apple, and Fitbit list their specific cleaning and care recommendations on their sites. Each stresses the importance of not submerging trackers in cleaning products or using soaps, which can get stuck inside the device and make them malfunction or cause further skin irritation.

Use a damp microfiber cloth to clean your watch or tracker face

Microfiber is lint-free and won’t scratch your screen. 

Allow your skin to breathe

Apple Watch’s wear guide recommends wearing the watch tighter while working out (so sensors can work properly to track things like heart rate) and loosening it after your workout is complete. 

“You want more air circulation, less moisture trapping, and less skin friction,” Varshavski said in his TikTok. He also recommends trying out bands that have holes for more air flow and better circulation if a normal rubber band isn’t comfortable.

You should also make sure your band is fully dry before returning it to your wrist.

If you’re doing everything you can to keep your tracker and band clean and dry and your skin is still irritated, check in with a doctor.

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