A Dirty Kid is a Happy Kid! Why Everyone Should Play in the Dirt



Evelyn returns from preschool, clothes covered in dirt; from her grandmas house stained from head to toe; from an outing with a friend, hands so dirty she could write her name with the grime under her fingernails. Apologies ensue. “I’m sorry she got so dirty.” or “I would have washed her if I’d had the time.” or “She sat down right in the dirt before I could stop her.”

And always I reply, “A dirty kid is a happy kid! PLEASE don’t apologize.”

Kids should get dirty. We are a part of nature. It is harmful to remove ourselves from it.

Bacteria is NOT the Enemy – So Much For the Hygiene Hypothesis

Bacteria has a bad reputation. We tend to think that any and all of it will hurt us. Parents keep immaculate houses in attempt to eliminate the “threat” of bacteria, washing hands with anti-bacterial soap, mopping with disinfectants, cleaning the counters with bleach. All of this is not only unnecessary but harmful to the immune system. It’s surprising just how many benefits there are to getting dirty.

1. Mycobacterium vaccae improves mood
There are millions of organisms living in the dirt but one that has been researched for its health benefits is called Mycobacterium vaccae (M. vaccae). This bacteria has been shown to allay depression.

It is not entirely clear why but researchers have found that contact with the bacteria releases cytokines which activate the nerves in our bodies to relay signals to the brain and release serotonin into the prefontal cortex – the part of the brain involved in mood regulation (exercise has been shown to have similar effects).

2. Mycobacterium vaccae is linked to higher IQ
This same release of serotonin that occurs when playing in M. vaccae laced dirt, has also been shown to improve cognitive function. The serotonin that is released while playing in the dirt temporarily boosts the IQ so that learning is facilitated. Maybe rather than making kids listen to Mozart before a test, we should send them out for recess.

3. Staphylococci heals wounds
Staphylococci often gets a bad rap but it has it’s benefits as well. Staphylococci can prevent inflammation. After an injury if staphylococci is present on the skin, the redness and swelling which often accompanies cuts and scrapes can be prevented. Forget the ointment, just use a good smearing of dirt before you bandage up!

4. Soil microbes boost the immune system
Playing in the dirt introduces the immune system to bacteria which it can then store in memory. The memory of the immune system is protects a growing body from getting sick later in life. A strong immune system also provides resistance to allergies. Getting outside more, rather than staying in more, might actually help reduce allergies.

5. Clay improves digestion
Dr. Weston A. Price noted in his book Nutrition and Physical Degeneration that clay was “the treatment used by several primitive races for preventing and correcting serious disturbances in the digestive tract. This consisted in the use of clay or aluminum silicate which modern science has learned has the important quality of being able to adsorb and thus collect toxic substance and other products…”

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  1. aloha Peggy ~ another great article! …and another helping of mud pie, pleeeease! ;) btw- when are you coming out with a “How To Primal Parent” book??? there is NOTHING out there!! Mahalo nui for courageously sharing your amazing pregnancy/parenting experiences & knowledge on your blog! me ke aloha pumehana, with warmest aloha ~Julie

  2. Aloha Julie! Thank you for reading with a forgiving eye.

    As a matter of fact, I am working on that book you describe right now at 11:33pm mountain time. Two more months till it’s finished I hope!

    • Unfortunately though, I think it should be noted that germs are not the only “dangers” lurking in soil. I have always been a strong advocate for letting kids get dirty and my kids love to dig holes three feet deep in the sandbox or drive their cars in the dirt in the yard (I’m not the best landscaper lol). BUT, what I have gotten for my free and easy attitude is a baby, and possibly older kids too who have very high lead levels. Pollution in the soil is a nasty fact of modern life and has come back to bite me in the butt. Luckily we caught it early enough before serious damage was done, but the effects of chronic lead poisoning can be devastating. Just something to think about. Sadly now I’ve been thinking of ways to keep my outdoor kids out of the dirt…

  3. omgoddess! I can’t wait (and I know I’m not alone in this feeling!) no doubt there will be a HUGE response! are you selling on Amazon or will it be an e-book on your blogsite here? inquiring minds want to know! ;)

  4. Love this. My three girls and I are the dirtiest things in three counties, hands down (dirty hands down!).

  5. That brings to mind images of open fields, rivers, and tree climbing. Your girls must be lucky (and happy)!

  6. Very interesting.

    Be careful where you play though.I know a mother who´s child almost lose vision due to infection with a parasite or bacteria from a playground. Probably it was in sand, I don´t remember.

    This post made me want to take off the shoes in the park when I go to run, but there are lots of dogs and most owners do not pick up what they leave.

    Also, I can´t lay my naked back on the grass, it itches.

    • Pathogens are definitely out there. But fear of bacteria is exactly what I am trying to discourage. Kid’s immune systems need a chance to become robust enough to fight those pathogens and with a diet free of grains and sugar, they will have a much better chance at doing that.

  7. Once the weather warms up, my little man loves to go out in the back yard and play in the mud.

    It used to concern me a bit, until I read that playing in the dirt is actually good for you!

    I suppose it is the same with using anti-bacterial soap on a regular basis. Sometimes, you can have too much of a good thing.

    • That’s good news! I don’t think a kid can get too much of playing in the dirt, though!

  8. I don’t post often and just found your site from Daily Apple. But kids are happier playing in the dirt! I was a professional nanny and Carolyn (at the time, 18months) would go to the park in the afternoon. She didn’t like to swing in the baby swings so I would swing with her in my lap on the big kid swings. Well this particular day, a storm had gone through the night before and there was a big puddle underneath the swing. She wanted to play in it so I let her. She was so happy, it kept her occupied for a good hour at least.

    Meanwhile all the other kids kept coming over wanting to play in the puddle and every mother kept dragging their child away giving me the dirtiest looks, haha. Anyway, when it was time to go, I just took off her clothes, put on a new diaper and buckled her into her car seat. Hey, she was happy and it is just clothes that will wash. Play in the dirt!

  9. Great article Peggy.

    My wife and I was only discussing this issue the other day.

    I grew up in an enviroment surrounded by mining waste (I lived in a small mining village in the UK). However everyday me and my friends use to explore the local woods, streams and waste heaps playing hours and coming home filthy. We never appeared to get ill, other than the usual children infections that you catch once to develop an immunity against the virus/bacteria.

    My mother was always an advocate of children getting dirty and still is today with her greatgrandchildren.

    I believe that we are becoming too steralised in life which is contributing to further complications. Where have all the hospital super bugs come from? They were never around when the cleaning consisted of a good mop with water and detergent.


    • Stacey,

      Great anecdote. I wish more parents could transcend materialism and see that clothes aren’t more important than the smiles on their kids faces.


      Unfortunately, neighborhoods have changed a lot for most kids. I grew up around fields and streams and cow fields. I was always dirty too playing in the trees and the dirt. Now, my parent’s old neighborhood is all houses and businesses. Getting dirty isn’t as available as it used to be.

  10. Correction: “mopping”

    ” moping with disinfectants”.

  11. Nigel

    Thank you for the constructive criticism. However I would “mope” with alcohol or chocolate not disinfectant.

    • Also suggest “sterilised” (or “sterilized”[USA]).
      The topic brings to mind the satirical film “Mon Oncle” (1958 – see IMDb article)

      “The title, Mon Oncle, should direct our attention to the nephew, for whom Hulot is a parole from the prison of his sterile house, enabling him to run with the kids, get dirty, buy doughnuts from a grubby vendor who applies the icing sugar with a bare hand and play practical jokes on passers-by (with Hulot ready to cover for him if need be). Fifty years later these comments are even more biting as we look at a whole generation of children raised in this kind of inhuman antiseptic environment: overweight, with eating disorders and allergies, socially inept with only a TV and a video game for a friend. Makes a dachshund in a red coat want to run with the mutts and tip over a garbage can or two, doesn’t it?”

  12. My kids are great dirt lovers, and we bought an aging house just because it came with 1/2 acre of property for them to run around in. Each child has eaten food straight from our garden without washing it first, and have happily kept the worms and snails they find as pets.
    Although I sometimes lament the amount of laundry I do, I am pleased to report that neither child was sick ALL WINTER this year.
    Thanks for your great article!

  13. My kids have always loved to be barefoot and enjoy dirt too. As soon as my youngest daughter gets to an outdoor space, off go the shoes. People look at me with fear of what ‘might’ happen. However, I watch her more confidently climb, run and play than others because she is in touch with the earth, her surroundings. They have all over the years created with mud and no doubt ingested dirt which have helped create happy, healthy kiddos!
    When I was in an eco village some years ago it was raining as we were doing some moving on a new site. There was so much rich, smooth clay that we were all slipping and sliding. I took off my shoes and had it all over my feet, legs and body. I slept in the tent that night without cleaning it off because we were in the woods. The next time I showered my skin was so smooth and felt amazing!
    I drink/eat clay too! It helps to detoxify my body from allergens and remove the toxic reactions within minutes.

    • How cool! That reminds me of where I grew up in California. There was clay everywhere.

  14. My two kids have played in the dirt at home, at parks, on vacation at the beach, everywhere. I have always encouraged them and allowed them to get dirty and no problems have arisen from it. They are very healthy and rarely get sick. I think mothers’ reactions to dirt and dirtiness is misguided.

  15. Great article! I miss playing in the woods and in my grandparents garden. And I bet dirt clod wars like we used to have are a thing of the past. I’m going to make sure my little girl gets some dirt in her finger and toe nails! :)

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