A Little Dirt a Day Keeps the Doctor Away!

As part of my son's exploration of the world, we often go outside so that he can take in the wonders of nature.  But, as he develops the abilities to be more hands-on, he has begun to "take in" nature in a whole new way.  The other day, I let him sit in the grass so he could feel it on his feet and pull at it with his hands.  Being Autumn, he is surrounded by leaves.  Previously, when he was little and just starting to learn to grasp, I would take him up to plants to touch the leaves.  But now, here they were all around him to touch and to hold...and to put in his mouth.

Unlike most mothers I see, I laughed.  "That's not food, silly," I said.  But he kept right on sucking on the leaf.  Eventually, he got bored with it and picked up something else.  On with his exploration.  I plucked a blade of grass.  He tried it and tossed it.  I smiled.  My husband came home from work to find us playing, and I boasted to him, "so many mothers would rip these leaves away from him, but I know better."  "Aren't you worried about botulism?" he asked.  I made some weird scoffing sound and laughed him off.  But, wait, I thought, do I really know everything I need to know about dirt?  Off I went to prove him wrong...hopefully.  My little guy did put a number of leaves in his mouth.

And luckily, as I suspected but only now have the factual knowledge to support, dirt is good for our kids!   As many of us know and have witnessed, babies explore the world with their mouths.  Their sense of touch his strongest here, and it helps them explore shape, texture, and so much more about the objects they come into contact with.  However, it's also nature's own built in way of creating a strong and tolerant immune system.  When it comes to the immune system, the maxim use it or lose it definitely applies.  Studies forming the hygiene hypothesis, believe that exposure to bacteria and viruses in dirt is what helps use develop our immune system in order to fight off a host of diseases.  Too much cleanliness leaves young children's immune systems weak and unable to fight things they come into contact with. Additionally, contact with these kinds of things teaches the immune system what to pay attention to and what to ignore.  For more scientifically collected information, Mary Ruebush, a microbiology and immunology instructor, wrote her book Why Dirt Is Good: 5 Ways to Make Germs Your Friendsabout this very thing.

What I found most interesting, however, was that worms are a big part of training and developing our immune system.  Studies have used worms (and I don't mean earthworms but rather parasites) to attack autoimmune diseases.  There is evidence that these parasites help our bodies avoid autoimmune disorders like allergies, asthma, multiple sclerosis, Crone's disease, and others.  Autoimmune disorders are our bodies working against itself, and many scientists are finding that this is because the body doesn't know what it should be fighting.  The study of parasites is offering a lot of information on how our immune system develops.

Now, the hygiene hypothesis is still just that: a hypothesis.  And it's not accepted amongst the entire medical community.  However, if you google it, you will find a number of studies that do support it.  The FDA states that "the “hygiene hypothesis” is supported by epidemiologic studies demonstrating that allergic diseases and asthma are more likely to occur when the incidence and levels of endotoxin (bacterial lipopolysaccharide, or LPS) in the home are low."  The general conclusion seems to be that our over-cleanliness is not helping our bodies or our children at all.

This is not to say that cleanliness is a bad thing.  Washing our hands after using the bathroom and a healthy sanitation system are still incredible ways that our society keeps healthy.  The hygiene hypothesis in no way says to swing from one way to the other.  Rather, it says that too much cleanliness is the problem; we've swung too far the other way from a completely unsanitary society.  Those parents bleaching their houses to death trying to eradicate every germ aren't doing their children any favors.  Washing everything with antibacterial soap is even worse, because not only does it kill the germs that help build the immune system, but those same bacteria become resistant to the antibacterial solutions.  So while we are weakening immune systems, we are building stronger germs!

I'm not saying we should start serving dirt for dinner.  When I let my son eat leaves, I knew they were ones that had recently fallen to the grass and were not yet peed on by some creature.  What I am saying is that children need freedom to explore the world with their hands and mouths, without us constantly batting everything away from them out of fear of germs.  Yes, animal poop is bad to eat, but a stick in the mouth or a little sand...not so bad.  Nature designed our bodies to fight, but they need practice and training.  And, even more importantly, our babies need opportunities to explore nature the way they were designed to.