When you have a mini me running around, your first instinct is to keep anything and everything she touches as clean as possible. But according to science, you might actually be doing more harm than good since it turns out dirt is actually good for children.

University of Chicago-based scientist Jack Gilbert decided to dive into the "dangers" of germs after he had his second kid in his new book, Dirt Is Good: The Advantage of Germs For Your Child's Developing Immune System.

Gilbert discussed the importance of letting little ones play outside [1] and get some face time with furry friends without immediately fishing around for the sanitizing wipes in an interview with NPR [2].

"So going out into the backyard and playing in the mud, and then as soon as they're filthy, bringing them in and sterilizing their hands with antiseptic wipes, and then making sure that none of the dirt gets near their faces," he said. "Also, keeping them away from animals. . . . It's fine to wash their hands if there's a cold or a flu virus around, but if they're interacting with a dog, and the dog licks their face, that's not a bad thing."

Another added benefit of letting your kid get a little dirty? A decreased risk of allergies [3]. While an increase in technological development and modernization has given people some seriously improved living standards, it's also compromised the strength of babies' immune systems.

"In the past, we would have eaten a lot more fermented foods, which contain bacteria," he said. "We would have allowed our children to be exposed to animals and plants and soil on a much more regular basis. Now we live indoors. We sterilize our surfaces. Their immune systems then become hyper-sensitized."

He also had some thoughts on how parents can actually boost their kids' immune systems without chasing them around with hand sanitizer. He suggests ensuring your children eat enough leafy green veggies [4] and fiber and limiting the amount of sugar they ingest each day.

So the next time your kid wants to jump in the mud while he's playing in the yard, remember that it's OK to, as they say, "rub some dirt in it."