Smartwatches used to track fitness goals are packed with more bacteria, dead skin cells and dirt than people might realize – and most users don't think to clean the bands.
Experts have warned that this could put the 40 percent of Americans who own a device at risk of serious infections such as pneumonia.
The warnings are in response to a series of studies conducted by DailyMail.com, which aimed to discover whether tracker wearers are at risk of infections.
This included a small survey asking how often people washed their Fitbit or Apple Watch bands, along with a forensic experiment that showed an alarming proliferation of bacteria on some types of trackers.
Three out of five wearables we tested were found to be contaminated with alarmingly high levels of bacteria – which were growing rapidly.
The popular devices, priced between $50 and $700, are marketed as a must-have for any fitness fan, and claim to accurately track a range of health metrics such as heart rate, calories burned and of course, step count.
DailyMail.com has conducted studies to find out how much bacteria is lurking in your Fitbit or Apple Watch. After two days in a petri dish, the insects began to multiply in samples taken from rubber and plastic tires
But speaking exclusively to this website, a top biological scientist has warned that this pack could put wearers at risk of itchy skin infections.
“Buildup of bacteria and dirt can lead to itching, contamination of other materials and infections,” says Professor Nwadiuto Esiobu, a biological scientist at the Charles E. Schmidt College of Science in Florida.
'Over time, the bacteria become a reservoir of antibiotic resistance, a major problem in the treatment of infectious diseases.'
Antibiotic resistance is a growing global health crisis: it describes the process by which residual bacteria develop the ability to defeat the drugs designed to kill them.
Our findings come after a recent study found that 95 percent of wristbands contain harmful bacteria that cause boils, vomiting and diarrhea.
Prof. Esiobu and colleagues from Florida Atlantic University's Charles E. Schmidt College of Science found that of 20 cultured smartwatch wristbands, 95 percent carried harmful bacteria.
It's estimated that about 40 percent of Americans use some form of fitness tracker to monitor their progress, but experts say the wearables could put them at risk of serious infections.
The study published in the journal Advances in Infectious Diseases found that rubber or plastic wristbands in particular contained harmful bacteria, such as Staphylococcus and E. Coli.
Staphylococci can cause a skin infection that leads to boils, blisters and redness of the skin, usually around the mouth and nose.
If the infection spreads, it can cause pneumonia. Or, if ingested, the bacteria can cause food poisoning, leading to severe stomach pain and nausea.
According to the Cleveland Clinic, the bug can in rare cases damage heart valves, leading to possible heart failure.
Bacteria-laden smartwatches could endanger people who are more susceptible to disease, says senior author and professor of biological sciences at the Charles E. Schmidt College of Science Nwadiuto Esiobu, Ph.D. and her team wrote in the study.
The researchers are particularly concerned about healthcare workers wearing the watches – who could expose vulnerable patients to infections.
The study found that while rubber wristbands contained high levels of bacteria, contamination on metal bands, especially gold and silver, contained little to no bacteria.
For the first part of our research, we conducted a small survey among a group of 20-35 year olds who regularly wear fitness trackers.
When asked if they clean their fitness tracker, 12 said they never do, seven said they wash it every two weeks and one said they do it once a month.
After five days, the petri dish containing samples of the rubber and silicone bands was completely covered with yellow spores – a sign of fast-growing bacteria. However, the metal bands did not show any germs
Dailymail.com then looked for how many bacteria lurk on the different types of fitness trackers.
First we prepared five petri dishes: these are specially designed jars that contain substances that feed bacteria and help them grow.
Basically, if there is bacteria in the jar, you will see it. We then ran a wet cotton swab over the bands of five different fitness trackers – all smartwatches or Fitbits – to get a sample of potential bacteria.
There are two bands made of rubber, two of silicon and one of metal.
The swab was rolled on the petri dish to transfer the bacteria.
By the end of the first day, it seemed like no bacteria would develop, but as the days went on and the samples matured, it started to become clear that there was more going on than met the eye.
By the end of day five – the recommended ripening period – the petri dishes containing rubber and silicone band bacteria were completely covered in a yellowish substance, showing how full of bacteria they were.
Meanwhile, the same test, performed on a metal band, showed that it contained no bacteria at all.
The reason for the higher number of bacteria on plastic and rubber bands could be that their porous and static surfaces provide a better environment for bacterial growth, Esiobu and her team said in the study.
Certain watch straps that contain metals, such as gold, have antimicrobial properties, while alternative watch straps have fragile surfaces that can trap bacteria.
Cleaning your smartwatch daily is the best way to reduce bacteria and the chance of infection, and it can be as simple as washing it with soap and water.
A nurse, who goes by the name Jess Maria on TikTok, posted a message video on the platform calls on people to thoroughly clean their smart watches – especially after exercise.
“I just had a patient who got staph [Staphylococcus] infection to their Apple Watch,” she said in the video, showing viewers how to properly clean their watch band.
Miranda Todor, a recent nursing graduate who works at George Washington Hospital in Washington, DC, was one of only two respondents who admitted to cleaning her wristband daily.
“As a nursing student, we learn a lot about hygiene and disease prevention,” she told Dailymail.com.
“Hospitals are rated based on hospital-acquired illnesses such as pneumonia.”
“I could have patients with MRSA infections, Covid, c-diff or pretty much anything you can think of,” Todor continued.
Todor said wearing her smartwatch while at work makes it easier to take vital data, but she makes sure to clean the band on the inside and outside of the watch with alcohol wipes as soon as she gets home each day.
“I don't really want to take any of that home with me,” she said.
The most effective way to thoroughly clean your smartwatch band is to wipe it down with Lysol Disinfectant Spray or alcohol wipes, which are proven to kill 99.99 percent of E. coli and staph bacteria after just 30 seconds of wiping .