Microbiological and health related perspectives of geophagia: An overview

Geophagia, which refers to the deliberate eating of soil, is considered to be a deviant eating disorder, a sequel to poverty and famine but could also be observed in the absence of hunger and in both scenarios may be associated with high degree of mortality and morbidity. The phenomenon has been reported to be common among pregnant women, lactating women, school children and people with psychiatric disorders. The microbiology of soil shows a broad diversity and functionality of soil microflora which impact variously on soil and its consumption. Soil microbes contribute immensely to the quality of soil and even determine soil types. Geophagia may be beneficial or harmful. Beneficial aspects include the use of kaolin to treat diarrhea, gastritis, colitis, enhancement of bioactivities and maintenance of normal intestinal flora by commensal flora found in soil. Clay or soil containing special constituents are valuable oral and topical antimicrobials as well as adsorbents of toxins. Microbiological underpinnings of geophagia include the ingestion of eggs of parasitic worms such as Ascaris lumbricoides, Trichuris trichiura with the health consequences. Highly toxigenic bacteria such as Clostridium perfringens, Clostridium tetani, Clostridium botulinum, the causative agents of gas gangrene, tetanus and botulism and other human pathogens may be ingested. It has also been postulated that indirect consumption of soil may pose serious health problems. For example, nitrate run-off and leaching from soil into water bodies may lead to eutrophication and colonization by toxic cyanobacteria with ripple medical effects such as gastroenteritis. Some general health implications of geophagia include association with iron deficiency and anemia, intestinal obstruction, constipation, peritonitis, dental damage, eclampsia, iron deficiency and even mortality. The interplay of factors involved in geophagia, though varied, intricate and researched may not have been fully elucidated. Further concerted efforts aimed at multidisciplinary research are warranted so as to address gaps in the corpus of knowledge on the important subject.