Geophagy: The consumption of soil, ground up rock, termite-mound earth, clay and dirt.
Clay is an extremely effective medicine; it is especially efficient at removing toxins from the body. In turn increasing overall health and vitality.
History of the Human use of Clay
Clays have long been used as a detoxifying substance in traditional medicine as well as in food preparation. (Engel, 2003)
Humans have been eating earth for at least forty thousand years and still occurs regularly among contemporary indigenous peoples, including the Aboriginals of Australia and the traditional peoples of East Africa and China, as well as in the West.
(Abrahams and Parsons, 1996)
Members of the Ottomac tribe along the Orioco valley in South America regularly consumed clay in large quantities, sometimes half a pound at a time! (Abrahams and Parsons,1996)
The Indians of the American southwest combine clay with wild potatoes to remove the toxic alkaloids, the aborigines of Australia use clay to remove the bitter taste of alkaloids from roots of the haemodorum species. (Engel, 2003)
Animals and Clay
Why is animal behavior important? Animals are similar to us physiologically and behaviorally. Therefore, studying them can allow us to learn more about ourselves.
Mammals, birds, reptiles and invertebrates have been observed eating dirt on every continent except Antarctica. (Which makes sense because of the shortage of exposed earth) (Engel, 2003)
Some animals do eat earth to obtain minerals such as salt (sodium chloride) lime (calcium carbonate) copper, iron and zinc. And sometimes they need these theses minerals for detoxifying foodstuffs. But Current research shows that often geophagy is performed as a self-medication practice.
Additions of bentonite clay improve food intake, feed-conversion efficiency and absorption patterns in domestic cattle by 10-20 percent. Clay fed cattle suffer less diarrhea (natural response of body to rid of toxins) and fewer gastrointestinal ailments than other cattle. In Venezuela, free ranging cattle help themselves to clay by digging out and licking at subsoils. (Kruelen, 1985)
Mountain gorillas in the Virguna Mountains of Rwanda eat volcanic rock. They were found to be much more likely to eat this earth during the dry season when their diet changed dramatically to bamboo, Lobelia and Senecio plants which all contain more toxic plant secondary compounds then their usual diet. Along with this change in diet came an increase in diarrhea. This consumption of earth is suggested to be a response to the seasonal change in diet. It turns out that this earth has a clay content of up to 15% Halloysite and is the type of clay found in the subsoil eaten by these gorillas. This specific clay is very similar to kaolinite the principle ingredient in Kaopectate, a pharmaceutical commonly used to soothe human gastric ailments. (Schaller, 1964); (Fossey, 1983).
Wild chimpanzees at Mahale in Tanzania take regular mouthfuls of termite mound soil and sub soils. When studying the health of these chimps scientist found that they we all suffering from diarrhea and other signs of gastrointestinal upset. The termite mound soil they are eating happens to be high in clay, around 30%. And is the same sort of clay eaten by the mountain gorillas. The termite mound soils appear to be a source of soothing medicine, used by chimps, giraffes, elephants, monkey and rhinoceroses. Many human populations also eat termite mound soils when the have diarrhea such as the Australian Aborigines. (Mahaney et al., 2000)
In the rain forests of the Central African Republic forest elephants regularly feed on high clay content earth. These elephants feed primarily on leaves all year round expect for the month of September when ripening fruit is very abundant so they eat primarily fruit. Leave generally contain secondary compounds designed to deter herbivores from feeding on them. The only month in which the elephants reduce there visits to the clay sites is during this fruit eating month of September. (Klaus et al., 1998)
James Gilardi and a team of scientists proved that Macaws eat clay in order to deactivate plant toxins. They found the seeds macaws eat contained toxic plant alkaloids. They feed one group of macaws a mixture harmless plant alkaloid (quinidine) plus clay and another group was feed just the alkaloid. Several hours later, the macaws that had eaten the clay had 60 percent less alkaloid in their blood than the group that did not eat the clay. (Gilardi et al., 1999)
When rats are fed the lethal pesticide paraquat, they eat montmorillonite clay (fuller’s earth) which adsorbs the poison. Posined rats that are denied access to clay do not survive. (Engel, 2003)
Side note: When behavioral responses to toxins are better understood we may be able to use the frequency of animal self-medication as an indicator of pollution in an ecosystem.
How Clay Works
The specific structure of clay allows it to bind to other molecules so effectively. Two or more miner-oxide layers lie in parallel. (Engel, 2003)
In the body toxins are deactivated by binding to clay particles, which are then excreted via feces. (Engel, 2003)
Clays can bind mycotoxins (fungal toxins) endotoxins (internal toxins) man-made chemicals and bacteria. They also protect the gut lining acting as an antacid and absorbing excess fluids. (Engel, 2003)
Taken orally, bentonite clay is used to detoxify the digestive system, eliminate intestinal parasites, strengthen the immune system, and fight free radicals. It also helps remove heavy metals from the body and assists in the process of liver detoxification.
Bentonite clay is created naturally from the combination of volcanic ash minerals called montmorillonite and ocean water.
Engel, Cindy. Wild Health: Lessons in Natural Wellness from the Animal Kingdom. Boston: Houghton Mifflin, 2003. Print.
P.W Abrahams and J.A. Parsons, “Geophagy in the Tropics: A Literature Review,” Geographical Journal, 162(1) (1996): 63-73.
D. A. Kruelen, “Lick Use by Large Herbivores: A Review of Benefits and Banes of Soil Consumption,” Mammal Reviews, 15(3) (1985): 107-123.)
G.B. Schaller, The Year of the Gorilla (Chicago: University of Chicago Press, 1964); D. Fossey, Gorillas in the Mist (London: Hodder and Stoughton, 1983).
W.C. Mahaney, R. G. V. Hancock, et al., “Geochemistry and Clay Mineralogy of Termite Mound Soils and the Role of Geophagy in Chimpanzees of Mahale Mountians, Tanzania,” Primates, 37(2)(1996): 121-134. For a review of geophagy in primates, see R. Krishnamani and W.C. Mahaney, “Geophagy Among Primates: Adaptive Significance and Ecological Consequences,” Animal Behavior, 59 (2000): 899-915.
G. Klaus, C. Klaus-Hugi, and B. Schmid, “Geophagy by Large Mammal at Natural Licks in the Rain Forest of the Dzanga National Park, Central African Republic,” Journal of Tropical Ecology, 14 (1998): 829-839.
J.D. Gilardi, S. S. Duffey, et al., “Biochemical Functions of Geophagy in Parrots: Detoxification of Dietary Toxins and Cytoprotective Effects,” Journal of Chemical Ecology, 25(4) (1999): 897-919.)