Hey, it's Kathleen Davis, and you're listening to Science Friday.

Today on the show is Grime Good for Kids.

We asked you, our listeners, to tell us the grossest thing your kids have done.

Hi, my name is Cheryl.

I'm calling from Bozeman.

My son, I one time caught him out at the barn. He was about three years old. And he was eating fresh llama poop, putting them in like one pellet at a time, like they were raisins. And he had, his mouth was covered with this like green

black goop. Cheryl, thank you so much for selling your kid out for the story. You may have

heard that a little dirt is good for kids. It helps them build up their immune systems and it sets

them on a path to future health. But what type of filth does the trick? Is a little

llama poop good for the gut? Here to answer those pressing questions and dig into the latest

science into the benefits of exposing your kids to the outdoors are my guests. Dr. Jack Gilbert,

microbiologist and professor at the Scripps Institution of Oceanography and in the Department

of Pediatrics in UC San Diego School of Medicine and Dr. Amber Fife Johnson,

Associate Professor and Pediatric Epidemiologist at the Institute for Research and Education

to Advanced Community Health at Washington State University based in Spokane.

Thank you both so much for being here.

My pleasure. It's exciting to be here.

Thank you so much. What a treat.

Okay, before we really jump in, I want to ask you to what are your thoughts on Cheryl's call?

Are you as horrified as I was when I first listened to that?

I'll just start by saying, um, filth, I don't know, man.

We probably shouldn't be exposing the kids to filth,

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