Young girl playing in the dirt



gut health

Immune System


Let Them Eat Dirt!

4 min read


Letting your children taste their “dirt creations” might not be a bad thing! Childhood is all about exploration and play. Many of our fondest childhood summer memories involve going barefoot, and playing in the dirt. Did you know that cultures all over the world actually eat dirt, and it is perceived as completely normal?

In fact, our cultural fear of dirt is negatively impacting our microbiome! Should you let your kids play in the dirt and maybe even taste test their mud pie creations? According to Chris Kresser, author of Your Personal Paleo Code:

Our culture’s obsessive attention to cleanliness, sanitation, and hygiene may actually be having unintended consequences on our immune system. While a sanitary environment may be crucial in areas such as hospitals or food production, our general avoidance of dirt, bacteria, and other infectious agents may be causing our under-stimulated immune system to become over-reactive to benign antigens.”

“Eating dirt” is associated with protection from chemicals, parasites, bad bacteria and toxins. Young, Sherman, Lucks, and Pelto,1 studied different cultures that regularly consumed dirt. Eating dirt did not parallel changes in nutrient requirements, and occurred most frequently in tropical areas (where pathogen densities are highest). In primates, eating dirt was associated with both protection of toxins and obtaining of nutrients.

According to Starks and Slabach,2 a common explanation for why animals and people eat dirt is that soil contains minerals, such as calcium, sodium and iron, which support energy production and other vital biological processes.

The fact that an animal’s need for these minerals changes with the seasons, with age and with overall health may explain why geophagia (eating dirt) is especially common when an animal’s diet does not provide enough minerals or when the challenges of the environment demand extra energy.” Scientific American, Would You Like a Side of Dirt With That?

Therefore, for some cultures eating dirt may be a way to gain back the trace minerals that are lacking in their diet.

Another hypothesis is that eating dirt is probably a good way to detoxify the stomach and gut from foods that contain small amounts of toxins. Clay-like soil in particular binds to toxins and prevents them from entering the bloodstream.

Getting dirty can also make you happy!

There are actually microbes in soil that help boost serotonin levels and thus elevate the mood. There is a specific soil bacterium, Mycobacterium vaccae, that may be able to alleviate depression.3

This bacteria activates a set of serotonin neurons in the brain. These are the same neurons targeted by antidepressants like Prozac. When out gardening or even just walking in dirt, one actually inhales the bacteria particles, even if there is no topical contact. The natural effects of the soil bacteria antidepressant can be felt for up to 3 weeks!

So does this mean we should go outside and start eating dirt? Realistically, this is not a good idea. There are still “bad” organisms in soil, and we are not recommending that. However, there is evidence to suggest that getting out in the dirt, and getting dirty is actually a good idea! In fact, over sanitizing and cleaning does have an adverse affect on our microbiome, especially during infancy and childhood while the immune system is still under development.

Rather than fearing dirt and keeping our youngsters “scrubbed clean”, let’s change our mindset!

Get outside and plant some vegetables or flowers, walk barefoot in the grass, or get out and play in the dirt with children. Keep your kids busy by ordering three extra large mud pizzas with your favorite toppings, like grass and dandelions! If you live in the city, consider a small city garden or even plant boxes. Just be sure to use organic soil that has not been treated with chemicals. The bonus is that you will improve your health and your mood, while enjoying the great outdoors!


About the Author:
Kathryn is a functional nutritional therapist, author, editor, and mama of two boys. She enjoys spending her free time out in nature-hiking and fishing. You can find her at and her book “Forties on Fire” can be found on Amazon.


  • 1. Sera L. Young, Paul W. Sherman, Julius Beau Lucks, and Gretel H. Pelto, 2011. Why on Earth?: Evaluating Hypotheses about the Physiological Functions of Human Geophagy. The Quarterly Review of Biology, 2011; 86: 2
  • 2. Starks, PT, and Slabach, B, 2012.Would You Like a Side of Dirt with That? Scientific American, Volume 306, issue 6. Scientific American
  • 3. Glausiusz, J, 2007. Mind and Brain/Depression and Happiness-Raw Data “Is Dirt the New Prozac?” Discover Magazine