That's a good thing, a group of North Carolina researchers says after studying more than 500 belly-button swabs, some from their own navels.
Most of the tiny critters in that "jungle of microbial diversity" are harmless, the researchers say, and lots of them actually kill off their disease-causing cousins.
Not just numerous, they also are diverse: 2,368 different types identified so far, with everybody's belly button carrying a different cast of characters.
Those are among findings of the Belly Button Biodiversity Project, an effort by researchers at North Carolina State University and the North Carolina Museum of Natural Sciences, both in Raleigh.
Magnified mug shots of the bacteria are posted on the project's website, wildlifeofyourbody.org -- along with an article detailing the likely critters crawling on pop superstar Lady Gaga.
"Your belly button is a great place to grow up if you're a bacterium," said cardiologist Dr. Tom Kottke at Regions Hospital in St. Paul. "It's warm, dark and moist -- a perfect home."
Gently washing your navel with soap and water regularly will lower the likelihood of bacterial problems, but you'll still have lots of microbial visitors in there.
So stay tuned: The new targets are armpit microbes and forehead mites.
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