Warning: Your sponge is more disgusting than you think.
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I know how often to change my sheets (once a week!) and how often to clean my coffee maker (every two weeks!)—and I'm really good at doing both. But one thing I'm not really good at doing is swapping out my kitchen sponge frequently enough.
And according to a study published in Scientific Reports, my lax sponge habits could be making me sick—or at the very least, making my dishes dirty—because my trusty old scrubber is probably covered in harmful bacteria. Here's exactly what the study found and how frequently you should actually be tossing your disgusting sponge in the trash.
In case you didn't know, your kitchen sponge is one of the dirtiest things in your house—potentially even more germ-ridden than your toilet. "Your sponge is the perfect breeding ground for bacteria," our senior lab testing technician, Jonathan Chan, explains. "Think about it: It gets regular exposure to water, food particles, and is porous."
The study found that there were 362 different types of bacteria on the average kitchen sponge. Not only that but half of the most commonly found germs on the sponges were disease-causing. Not exactly what you want to be washing your dishes with...
Every week, according to the study's scientists. However, it depends on how frequently you use your sponge and what you use it for. A.k.a if you use your sponge every day, you'll want to change it more often than if you're only using it twice a week. The same rule applies if you use your sponge to clean surfaces with raw meat (which Jonathan recommends avoiding because "the bacteria is just too dangerous to mess with").
No matter how often you do (or don't) replace your kitchen sponge, there are ways to keep it cleaner for longer or at least give it a quick refresh. One of the most popular hacks is to microwave your slightly-wet sponge for one to two minutes. However, this method isn't as effective as you might think—the same study reported that microwaving a sponge only killed off about 60 percent of the germs.
Instead, we recommend placing your sponge on the top rack of your dishwasher and turning it to the "heated dry" setting. You can also soak your sponge in a vinegar bath or a diluted bleach solution (use 1/2 cup of bleach for every gallon of water) for about five minutes to help sanitize it.
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