Fun with Science Club®


			Pregnant women eat clay to stay healthy. Beth Tyler 05.07.01 Many species of animals, including some monkeys and birds, eat clay from the earth. The eating of clay, or geophagy, is also common in some human populations. Anthropologists have observed that pregnant women especially like to eat clay. Many people in the United States think this is weird or gross, but clay actually provides important nutritional benefits to some pregnant women. Anthropologists Andrea Wiley and Solomon Katz wanted to know where clay-eating was popular. Because clay has a lot of calcium in it (the same mineral found in dairy products like milk and cheese), they hypothesized that clay-eating would be most common in populations that didn't eat dairy products. They decided to test their hypothesis among African populations. First, they searched through all the papers they could find about the presence or absence of geophagy in specific African populations. Then they looked at whether or not these groups of people had dairy products. As their hypothesis predicted, Wiley and Katz discovered that pregnant women who don't eat dairy products were more likely to eat clay than pregnant women who do eat dairy products. The clay provides the women with needed calcium and many other minerals. They also found another interesting fact. Although many women in their first three months of pregnancy often throw up, women who ate clay were less likely to throw up than women who didn't eat clay. Clay-eating women are pretty smart. They keep themselves healthy by snacking on the earth.


			Wiley, Andrea S. and Solomon H. Katz. 1998. Geophagy in pregnancy: a test of a hypothesis. Current Anthropology, 39(4): 532-545.