Geophagia

Geophagia is the consumption of dirt. Like Coprophagia, it is dangerous because parasite eggs can be passed in animal feces.

Baylisascaris eggs, for instance, are dropped millions at a time by raccoons and other wildlife. They can stay dormant for years, through extreme temperatures and drought. Some of these roundworm eggs may remain in the soil long after the feces have decomposed, and become active in the digestive tract upon being consumed. Children's predilection to engage in geophagia makes them more susceptible to worm infestations.

Other dangers associated with geophagia include damage to enamel, the ingestion of a variety of bacteria, lead poisoning and intestinal obstruction.

In some parts of the world, geophagia is a culturally sanctioned practice. In Uganda, for instance, earth intended for consumption is available for purchase.

Classification and Diagnosis

The International Classification of Diseases includes geophagia among eating disorders (F50) as a variety of pica, the ingestion of non-foods. However, dirt can constitute a source of iron, although the bioavailability of such mineral is quite variable. For example, red clays often have iron in ferrous form, poorly absorbed by humans.

Geophagia can be diagnosed, in absence of other evidence, by measuring the concentration of silica in feces.

References

• Reid R (1992): Cultural and medical perspectives on geophagia. Med Anthropol 13(4):337-51

• Harvey P, Dexter P and I Darnton-Hill (2000): The impact of consuming iron from non-food sources on iron status in developing countries. Public Health Nutrition 3(4):375-383

• Ziegler J (1997): Geophagia: a vestige of paleonutrition. Trop Med Int Health 2(7):609-11

• Walker A, Walker B (1997): Pica. J Soc Health 117(5):280-4

• Vermeer D (1966): Geophagy among the Tiv of Nigeria. Ann Assoc Am Geographers 56(2):197

• Hamilton G (1998): Let them eat dirt. New Scientist 159(2143):26-31

• Wong M, Simeon D (1993): The silica content of faeces as an index of geophagia: its association with age in two Jamaican children's homes. J Trop Pediatr 39(5):318-9

External links

• http://www.ingentaconnect.com/content/bsc/tmih/1997/00000002/00000007/art00067