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Medicine Beneath Your Feet: A Biocultural Examination of the Risks and Benefits of Geophagy

Published online by Cambridge University Press:  01 January 2024

Sera L. Young  and
Joshua D. Miller
Sera L. Young*
Affiliation:
Northwestern University, Evanston, IL, USA
Joshua D. Miller
Affiliation:
Northwestern University, Evanston, IL, USA
*
*sera.young@northwestern.edu
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Abstract

Geophagy is the intentional consumption of earth. Although widely documented among vulnerable populations, including children and pregnant women, the causes and consequences of geophagy remain poorly understood. Relevant literature was, therefore, reviewed to describe geophagy across species, geographies, life stages, and disease states. After a brief consideration of hypothesized etiologies, the potential harmful and beneficial consequences of geophagy are described, considering current evidence for each. Data available to date suggest that the greatest potential risks of geophagy include toxicity or heavy metal poisoning, and diseases resulting from consumed clays binding nutrients and beneficial pharmaceuticals in the gut. Evidence also suggests that geophagy may be beneficial by protecting against harmful pathogens and toxins through two distinct physiological pathways. Future research should explore causal relationships between geophagy and iron deficiency, as well as investigate the biological and psychosocial conditions that govern geophagy.

Keywords

AnthropologyBioculturalCross-culturalDetoxificationGeophagyHistoryNutritionPathogensPicaSupplementation
Type
Research Article
Information
Clays and Clay Minerals , Volume 67 , Issue 1 , 15 February 2019 , pp. 81 - 90
Copyright
Copyright © Clay Minerals Society 2019

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