Geophagia, a soil - environmental related disease

Abstract

Geophagia or geophagy is a habit for an uncontrollable urge to eat earth that commonly is occur in poverty-stricken populations and particularly there are in children under three years of age and pregnant women. The custom of involuntary or deliberate eating of soil, especially clayey soil, has a long history and is amazingly widespread. Some researchers have described an anomalous clay layer at a prehistoric site at the Kalambo Falls in Zambia indicating that clay might have been eaten by hominids. Von Humboidt reported from his travels in South America in early 18th century that clay was eaten to some extent at all times by the tribe in Peru. In the mid 19 century it was customary for certain people in the north of Sweden to mix earth with flour in making bread whether the clay effected an improvement in taste. In Iran, geophagia has seen in some of children and pregnant which that is solved with eating starch daily. For example, some reports are shown that there has been geophagia disease in some parts of Fars province, around Shiraz city which have been made different health as well as environmental complications. Clay with a large cation exchange capacity that is also fairly well saturated can release and supplement some macronutrients and micronutrients such as Cu, Fe, Mn and Zn. Deficiency of these elements led to dwarfism, hypogonadism, anemia, hepatosplenomegaly and skin problems. Almost all of these health complication evidences are seen in most of people who has been suffered from geophagy in Iran. However, geophagia has a history of 2000 years and the effects of soil and environmental chemistry on human health have been studied for hundreds years ago in China. In this review it has tried to introduce the geophagia as a nutritional and environmental complication in Iran as well as in the world which could be a serious health risk for human.