Everyone always says you should wash behind your ears. But what about inside your ears? You should pretty much never clean those, and trying sends more people to the hospital every year with cotton swab–induced injuries than show up with wounds from razor blades, according to Real Clear Science. Here’s the basic problem:

For the most part, swabs merely condense and impact the earwax further into the ear canal, where it can cause pain, pressure, and temporarily poor hearing. “There’s no need to clean your ears with a cotton bud,” writes Dr. Rob Hicks. “The ear has its own internal cleaning mechanism. Fats and oils in the ear canal trap any particles and transport them out of the ear as wax. This falls out of the ear without us noticing.”

Besides, ear wax isn’t dirt. It’s supposed to be there, says the American Hearing Research Association:

First, one should realize that wax isn’t all that bad. It keeps your ear dry and helps prevent infection. Thus, you don’t want to eliminate wax; you want to keep it from blocking your ears.

The Telegraph says:

“In most circumstances, wax is actually beneficial to the ear,” says Simon Baer, a consultant ear, nose and throat surgeon at the Conquest Hospital in Hastings. “It causes foreign bodies to adhere to it, preventing them from going further into the ear, and it has anti-bacterial properties. Removing it is like taking the wax off the surface of polished wooden furniture. It makes the delicate underlying skin of the ear more susceptible to infection.”

Of course, some people have way too much earwax, but that’s rare. Certainly not common enough to support the huge earwax removal industry. The Wall Street Journal writes:

Some 12 million Americans visit medical professionals annually for earwax removal. Millions more have it done at spas and ear-candling parlors, which theoretically suck out earwax with a lighted candle. North Americans also spent $63 million last year on home ear-cleaning products, from drops to irrigation kits, according to market research firm Euromonitor International.

Removing wax yourself can be dangerous, though. Thousands of people go to the hospital every year because of those pesky cotton swabs. So not only is it doing nothing for you, it’s actually perhaps hurting.

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