In 1581, a criminal set for execution by the name Wendel Thumblardt offered his captors a deal. In lieu of executing him, they could test the purported magical effects of terra sigillata from the Greek island of Lemnos. The source of the belief was the ancient Roman medical researcher, Galen, who claimed that the red clay from Lemnos had medicinal qualities. The authorities in the 16th century agreed to Thumblardt’s offer. They gave him a poison along with the terra sigillata, and when he survived, they freed him.
I read this in a fascinating article by Daniel Mason in Lapham’s Quarterly, entitled Balanced Diets. Mason was in medical school when he wrote a novel, The Piano Tuner, and when the novel became a bestseller, he decided to stay a writer. His subject in the article is Pica, a medical disorder, defined on Wikipedia as “characterized by an appetite for substances largely non-nutritive (e.g., metal, clay, coal, sand, dirt, soil, feces, chalk, pens and pencils, paper, batteries, spoons, toothbrushes, soap, mucus, ash, gum, lip balm, tacks and other office supplies, etc.).” More specifically, geophagic pica, or the practice of eating earth. Here, in five acts, is a very brief modern history of pica.
Prior to the 19th century, pica, like hysteria, was considered a woman’s disease, and associated with chlorosis (the green sickness). Mason quotes Ambroise Paré, “physician to four French kings: ‘And when they are mature and ready for marriage, if menstruation begins but marriage is too long delayed, we find always that they are tormented grievously by a swooning of the heart and suffocation of the womb, particularly if they fall in love; their genitals feel warm, which arouses their desires and titillates and stimulates them, causing them to expel their own seed themselves. The seed, if it remains in the spermatic vessels or in the womb, rots and turns to poison…causing putrid vapors to rise to the higher parts and to pass into the blood…They feel pensive and sad and lose all appetite, their depraved appetite being called pica…They seem more dead than alive and often die dropsical and languishing, or mad.’” Cure for pica, thus, was – marriage.
In 1800, Alexander von Humboldt reported on a tribe in South America he had encountered near the Orinoco river. Two or three months of the year, when fishing was difficult, the Otomacs ate huge quantities of earth. What shocked the European educated world was not just that seemingly healthy people ate dirt, but that it was eaten by men. Not to worry, the open-minded scientists of Europe amended their views of pica. The disease afflicted, they said now, women and savages. For this there was abundant evidence. European slaveowners in the Caribbean had plenty of accounts of their slaves, who came from West Africa, craving charcoal, clay, chalk, mud, sand, rotten wood, shells, cloth, etc.
The problem with this view of pica, fascinating as it was, lay in the overabundance of evidence. For in seeking to explain it, scientists started finding pica everywhere. By 1849, Humboldt himself had to add to the earth eating peoples list Swedes, Finns, and even northern Germans during the Thirty Years War. It wasn’t just women and savages. Then in 1851, Otto Funke discovered hemoglobin as the carrier of iron in the blood, opening up research of anemia. Even prior to this scientist knew that pica could be cured with a hearty meal of red meat and vegetables, but now they understood why it occurred in the first place: lack of nutritional food caused low iron in the blood, causing a craving for the kinds of minerals that could regulate the problem. To quote Mason, “…there is an inherent beauty in this image of auto-regulation, this instinctual understanding of the mineral commerce that moves so invisibly through our blood.” Neat, huh?
Except that it’s a little more complicated. People with pica did not really crave foods high in iron, nor did they crave earth in general. “The Otomacs had not considered all clays “equally agreeable,” nor the “Negroes of Guinea” who sought vainly for caouac in Martinique. Across the world, the craved earths are mostly light-colored, crunchy when dry, aromatic when wet, easy to dissolve.” Nor could its prevalence be explained. Mason quotes Berthold Laufer, an anthropologist of the first half of the 20th century. “Laufer left little doubt that earth eating had “nothing to do with climate, race, creed, culture areas, or a higher or lesser degree of culture.” Indeed, to read Laufer is to watch a war of attrition remove all notions of Otherness from our understanding of pica.” Pica, then, is not of the other, perhaps not even a disorder.
Even Humboldt recorded cases of animals consuming earth. “Over fifty species of primates practice pica,” writes Mason. So he, along with contemporary scientists, offers an evolutionary explanation for pica (after all, we live in the age of the evolutionary explanation). Eating earth is a way to domesticate food, so to speak. Eating clay cuts out the bitterness of certain foods, claimed Laufer, and bitterness is often found in foods that are in some way poisonous. They clay neutralizes the poison, which is what happened in the case of Wendel Thumblardt in 1581.
And that’s the best we got. Pica is a vestige of an evolutionary response to poisonous food. What I love about this article is how the attempts at explaining the disorder say more about the scientists and their prejudices, or the paradigms of their age (and our own!) than they do about the disease. And what I love about pica is that it lies at the cross of biology and culture, and the mind and body. Pica may appear in nature and may be an evolutionary response, but how cultures deal with this varies based on particular conditions of climate, flora, fauna, etc. And although it has something to do with iron deficiency, how and why that deficiency is manifested in the mind that craves not just specific kinds of clay, but chalk, metal, wood, ice – remains a mystery.
Oh, I almost forgot. The word pica originates from the Latin word for magpie, because it was considered that the bird would eat anything. So here’s a picture of a magpie.