To find out what might be lurking in your showerhead, Inside Edition decided to do some testing, taking 22 swabs from 11 different showerheads.
Among those who volunteered were mothers Renee Diaz and Lara Alcantara.
"That's gross, it's black," Alcantara said as she held up a swab.
Inside Edition sent off the swabs to Virginia Tech University, where top microbiologist Joseph Falkingham oversaw the testing.
"Were you surprised by the results?" asked Inside Edition correspondent Diane McInerney.
"Yes I was," he answered. "There are some high numbers that worry me."
Then it was time to tell the mothers what had been found.
"Are you ready?" McInerney asked Diaz.
"Yeah, let's do it," she replied.
"Here's what we found ... fungus," McInerney said.
"Yuck," said Diaz.
"But that wasn't the worst of it," McInerney continued. "We also found it loaded with a bacteria called mycobacteria that can cause lung infections."
"Oh my god," Diaz said. "That's really scary, and I have kids."
Symptoms of such an infection include fatigue, fever and night sweats, which Diaz said she had been feeling of late.
"I've gone to the doctor and never thought that could be from my shower ever in a million years," she added.
What about Alcantara's results? Her showerhead not only had fungus but was also loaded with mycobacteria.
"I'm a pretty clean person," said Alcantara. "I would have never thought there would have been fungus or any other crazy bacteria on the showerhead."
Though it's not common to get sick from a showerhead, people with suppressed immune systems are more vulnerable.
But there is something you can do to protect yourself. Soak your showerhead in bleach for 30 minutes once a month and then thoroughly rinse it off.
"If you do that once a month, the mycobacteria are very low," Falkingham said.