Growing research suggests that our obsession with cleanliness might actually be making children sicker, not healthier.

Father Washing Baby's Hands in Sink
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"You have to eat a peck of dirt before you die," is a lot more than a silly old proverb. Growing research suggests that dirt isn't always the enemy, in fact, America's obsession with cleanliness might actually be making children sicker, not healthier.

Oklahoma Medical Research Foundation immunologist Dr. Eliza Chakravarty told The Oklahoman that an increase in "germophobic parenting" and sterilized environments may keep children's immune systems from developing properly.

"For your immune system to protect you, it has to know the difference in what is dangerous and should be attacked and harmless substances that can be ignored," Chakravarty explained. "And to learn that, it needs to be exposed to some of the elements we're erasing from the environment."

The theory that childhood exposure to germs and certain infections helps the immune system develop is called the "hygiene hypothesis." According to Mayo Clinic, this is how the body learns to differentiate between harmless and harmful substances.

While Chakravarty noted that handwashing, clean living, and vaccines are still important, she also added that "there's a difference between a healthy level of cleanliness and essentially living in a bubble."

The "hygiene hypothesis" proposes that an idle immune system will seek out things to fight, causing it to identify harmless substances like pollen, peanuts or pet dander as threats, and trigger an immune system overreaction. Autoimmune diseases like allergies and asthma occur when the immune system attacks the body's tissues as if they were invaders.

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"We need protection from serious illnesses, but kids need exposure to a wide variety of things that aren't actually dangerous," Chakravarty concluded. "Kids are going to eat dirt, and that's generally OK."