All in all, Utah State University anthropologist Carol Loveland wouldn't advise replacing meat and potatoes with a plate of microbe-infested dirt or clay.
But Loveland, who recently completed a study of geophagia - human dirt- or clay-eating - also acknowledges, reluctantly, there are rare instances when a mouthful of the right kind of soil is good for what ails you."Some soils may contribute minerals . . . that can be absorbed," she said. "(But) some people can become very anemic" from eating dirt, ingesting chemicals that interrupt the body's exchange of nutrients - or harmful microbes, even worms.
"I think the chances of clay-eating doing an individual very much good are rather slim," Loveland concludes.
Loveland said the geophagia study, to be published in the June issue of the scientific journal Food and Foodways, found examples of dirt- and clay-eating stretching back to pre-history.
"There may have been a point where food was not so much separated into animal or vegetable," she mused. "Whatever was available in the environment was edible."
In Roman times, Galen - the 2nd century physician known as the father of experimental physiology - acquired 20,000 lozenges made of dirt and goat's blood from the Mediterranean island of Lemnos and dispensed them for various ailments.
To this day, earth-eating is practiced in various forms, with its practitioners motivated by beliefs in the nutritional, medicinal, cultural or even religious properties of soil.
"In Africa, the clay is frequently formed into an egg shape and sold in the markets. In India, it's molded into the shape of a tea cup, left unbaked. Tea is poured into the cup and the individual drinks the tea and eats the cup," Loveland said.
In America's rural South, clay-eating remains a resilient subculture. While the practice may have been imported centuries ago by African slaves, Loveland emphasizes it can no longer be described as limited to particular social, ethnic or racial groups.