Abstract
Geophagia is the deliberate intake of a high dose of soils and clays (tens of grammes), mostly by women and children under the age of two. It is a controversial centuries-old practice, common to all societies yet deeply frowned upon by many. The craving for geophagic materials has never been satisfactorily explained. It is often regarded as a minority problem and, as a result, it has not attracted the research funding it should to tackle the problem. Geophagia may be beneficial or harmful. Beneficial aspects encompass the use of kaolin as antidiarrhoeals, and for the alleviation of gastrointestinal upsets, supplementation of mineral nutrients and relief of excess acidity in the digestive tract. Certain clays have been identified as having special constituents, valuable as oral and topical antimicrobials as well adsorbents of toxins. Geophagia has been associated with iron deficiency anaemia but it is not clear whether it is the cause or effect of the anaemia. Other health implications of geophagia include constipation, intestinal obstruction, dental damage, peritonitis and eclampsia. Whatever the possible benefits that may accrue from such a habit, the risk of ingesting the eggs of parasitic worms as well as exposure to highly toxic bacteria and heavy metal poisoning cannot be excluded. In the absence of in vivo research analyses of geophagic materials, the causes and effects of this practice may never be known.