Sealing off the entrance to your ears can increase the population of bugs.
Your ears are already dark, moist and full of oils and dead skin – an all-you-can-eat buffet for many bacteria. Sealing off the entrance with headphones or earphones seems like it could only make that environment more inviting to these microbes.
Indeed, a 2008 study at Manipal University in India found that frequent use of earbuds did increase the population of bacteria in the ear – mostly various strains of staphylococcus, a common skin bacterium.
And in 1992, a study at the Navy Medical Research Institute in Bethesda, Maryland in the US, found that the kind of over-the-ear headphones used by airlines had 11 times more bacteria after having been worn for just one hour.
As icky as this sounds, it isn’t necessarily cause for concern. The headphones in the second study had been sterilised before use, so began with a very low initial bacterial population and that 11-fold increase still resulted in a fairly low number in absolute terms.
Also, this increase was too fast to be accounted for by the reproduction rates of bacteria. The study’s authors concede that most of the bacteria must already have been present in the deeper skin layers and tucked into the sebaceous glands that produce ear wax. The dark warm conditions while wearing headphones just encouraged them to come out and play.
Furthermore, there’s no evidence that these bacteria cause any harm. A 2002 study of call centre workers in Malaysia found no link between headphone use and ear infections.
The germs that proliferate in your ear while you listen to music and podcasts, are the ones that live there normally, and your ear is well equipped to deal with them. Several studies have suggested that constantly inserting and removing earbuds or earplugs may increase the risk of skin abrasions that allow harmful bacteria to get in and cause infections, but there isn’t strong evidence for this yet.
Read more:
- How do noise-cancelling headphones work?
- Why does left and right matter on headphones?
- How can I stop my headphones tangling themselves into the Knot from Hell?
- Why do our ears ring after we listen to loud music?
Asked by: Rhys Cooombes, Plymouth
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