Why many coffee makers are crawling with germs and mold, expert says

Your morning cup of coffee might pack more than just caffeine, an expert says.

Germs, yeast and mold are lurking in your coffee maker if you haven't cleaned it properly, said Lisa Yakas, senior project manager of Consumer Products at the National Sanitation Foundation.

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Many people don’t clean and dry the appliance’s water reservoir, Yakas said.

“Some of these organisms like these moist and damp places, that’s where they like to grow,” she told USA Today. “If you eliminate that moisture altogether … then you eliminate their conditions to grow.”

Yakas recommends pouring out any unused water and then leaving the lid off the reservoir so it dries.

A 2011 study by NSF determined the coffee maker is the fifth germiest item in your kitchen. Nearly half the coffee makers it tested had yeast or mold in the water reservoir.

» 5 everyday items you're using that are germier than you think

If you’re thinking, “I’ll just get coffee at work,” you might want to keep reading.

Chuck Gerba, professor of microbiology at the University of Arizona, told USA Today that office break rooms have more bacteria than restrooms.

The coffee pot’s handle is the germiest part, Gerba said. If your office has a single-use machine, like a Keurig, he says, most germs are found on the top of the machine where you put the coffee pod.

The best way to eliminate germs and mold, Yakas said, is “keep it dry and keep it clean,” USA Today reported.

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