Of course, ingesting dirt can also be poisonous. Along with minerals and detoxifying materials, you might unintentionally ingest bacteria, viruses, parasitic worms, and dangerous amounts of lead or arsenic. Because of these risks, modern dirt eaters should stick with safe commercial products that have been heated or otherwise sterilized—but they should not be stigmatized for their behavior. Taken as a whole, the evidence argues that geophagia, in many cases, is not a sign of mental illness. It is a specific defense that has evolved to combat toxins and, possibly, ease mineral deficiencies. Although you may not be thinking about geophagia when you take vitamins or seek comfort from a swig of Kaopectate, you are in fact participating in the age-old practice of eating dirt.
This article was published in print as "The Scoop on Eating Dirt."