Speaker 1: Welcome to Brainstuff, a production of iHeartRadio. Hey brain Stuff.
Speaker 1: I'm Lauren vogelbaumb and this is a classic episode of
Speaker 1: the podcast. In this one, we dig no pun intended
Speaker 1: into the branch of paika called geophagy, that is, the
Speaker 1: craving and eating of dirt. It's perhaps surprisingly widespread, though
Speaker 1: still not well understood, partially because of sciences biases. Hey
Speaker 1: brain Stuff, Lauren Vogel bomb. Here in gas stations and
Speaker 1: flea markets all around the southeastern United States, you can
Speaker 1: find packets or boxes containing crumbles of white clay. In Kenya,
Speaker 1: you can buy reddish dirt on the street, formed into
Speaker 1: little pellets that look like baby carrots. In Uganda, you
Speaker 1: can buy Yankee Doodle brand dirt at the grocery store.
Speaker 1: A website called Earth's Clay Store sells clay from all
Speaker 1: over the world and ships them right to your home.
Speaker 1: But what are you supposed to do with it when
Speaker 1: it gets to you, Well, you eat it. You might
Speaker 1: have a vague sense that you've heard of people eating
Speaker 1: dirt before pregnant women. Maybe pica is the overarching term
Speaker 1: for craving and eating things that are not food. In
Speaker 1: the sixth century, ce, the physician Flavius Aecius noticed people
Speaker 1: sticking non food items in their mouths the way that
Speaker 1: magpies pica in Latin pick up random objects in their beaks.
Speaker 1: He figured these people had entirely indiscriminate appetites for just
Speaker 1: any old thing, and termed the behavior after the magpie.
Speaker 1: It turns out pika is kind of a misnomer because
Speaker 1: pika cravings are actually very specific, though according to the
Speaker 1: Diagnostic and Statistical Manual of Mental Disorders, or DSM, it
Speaker 1: includes a range of behaviors. Some people crave paper clips, batteries,
Speaker 1: or coins. These potentially dangerous cravings are considered by the
Speaker 1: DSM to be actual disorders, but pica can also include
Speaker 1: cravings for a rawstarch that's amylophagy, ice that's pagophagy, and
Speaker 1: dirt that's geophagy. Geophogy is one form of pika found
Speaker 1: in almost every country in the world. We spoke with
Speaker 1: Sarah Young, assistant professor in the Department of Anthropology at
Speaker 1: Northwestern University. She said, I was surprised when I first
Speaker 1: saw it. I was studying pregnant women ethnography in Zanzibar,
Speaker 1: and I asked a woman what she ate when she's pregnant,
Speaker 1: and in Swahili, she said, every day, I take earth
Speaker 1: from this wall and eat it. I was just learning
Speaker 1: Swahili and was pretty good at it, but I really
Speaker 1: didn't think I was understanding correctly. My research assistant was like, yeah,
Speaker 1: you heard right. Young ended up writing her PhD dissertation
Speaker 1: on geopogy and winning the Margaret Meade Award in twenty
Speaker 1: thirteen for her book Craving Earth, which detailed her research
Speaker 1: about geofogy practices worldwide. In her research, Young tracked down
Speaker 1: medical literature, historical texts, research on animal behavior, soil science,
Speaker 1: and parasitology, and came to the conclusion that there are
Speaker 1: four possible explanations as to why people eat dirt. The
Speaker 1: most common and longest running take on geofogy is that
Speaker 1: there's no good reason for it, that it's a pathology,
Speaker 1: it's an aberrant behavior of some unknown origin. Young explained
Speaker 1: the racism, sexism, and classism behind that simplistic take quote
Speaker 1: it's the women they know, not what they do explanation.
Speaker 1: It was basically white men writing about this for the
Speaker 1: past few hundred years, and it was dismissed as aberrant
Speaker 1: We can refute this. There are so many species of
Speaker 1: animals that go to great risk to get clay in charcoal,
Speaker 1: like the colobus monkey that steals charcoal from villagers. But
Speaker 1: even so, we know very little about geophagy because for
Speaker 1: centuries scientists were stubbornly lacking curiosity about it. When scientists
Speaker 1: did start looking into it, the first hypothesis they came
Speaker 1: up with to explain why hundreds of thousands of people
Speaker 1: worldwide crave and eat dirt is that there must be
Speaker 1: something useful in the clay, micronutrients of some kind. Young said,
Speaker 1: the mother Nature's multivitamin explanation is a really intuitive one,
Speaker 1: but unfortunately it doesn't really shake out for starters. Although
Speaker 1: the clay her study participants in Zanzibar were eating was
Speaker 1: tinged with red, indicating iron content, investigations into whether that
Speaker 1: iron could be absorbed and used by the body came
Speaker 1: up empty. Plus. According to Young, people generally prefer whiter clay.
Speaker 1: If you give a geophogist to the option of snacking
Speaker 1: on Georgia white calin or the reddish clay found on Zanzibar,
Speaker 1: they'll almost always pick the white kalin, which does not
Speaker 1: contain iron, So we turn to another hypothesis. Could dirt
Speaker 1: provide protection from germs. The explanation that eating dirt is
Speaker 1: somehow an immune system boost might not make sense on
Speaker 1: the surface. After all, we're supposed to stay away from dirt,
Speaker 1: wash our hands, clean our clothes, take off our shoes
Speaker 1: when we enter the house. But clay face masks can
Speaker 1: draw germs and oils and dead cells from your skin
Speaker 1: and they're made of dirt, right. According to Young, eating
Speaker 1: clay might collect stuff inside of the gut, similar to
Speaker 1: how a mud mask collects stuff from your face. But
Speaker 1: why would somebody need an intestinal mud mask. The answer
Speaker 1: is protection from pathogens and harmful compounds. Many harmful microorganisms
Speaker 1: and compounds can enter your body via the things you eat.
Speaker 1: You digest the food and it's absorbed through the wall
Speaker 1: of your intestine and into your bloodstream. But lots of
Speaker 1: potentially harmful stuff can get to us in this way too.
Speaker 1: Clay may stimulate the mucous membranes on the surface of
Speaker 1: your guts to create more mucus, thus forming a sort
Speaker 1: of protective barrier against those pathogens and compounds. Young said.
Speaker 1: It can also bind with whatever harmful thing you're eating.
Speaker 1: For example, in the Andes, people eat wild potatoes which
Speaker 1: contain these toxic chemicals called glycoalkaloids, but after they dip
Speaker 1: the potatoes in clay, they become safe to eat. But
Speaker 1: while eating clay might protect from pathogens and harmful chemicals,
Speaker 1: which is especially important in pregnant women. There's something of
Speaker 1: a Goldilocks principle at play here. You want to shield
Speaker 1: yourself from the harmful stuff, but you also don't want
Speaker 1: to protect yourself from the nutrients you need. For example,
Speaker 1: if you eat a steak that's full of both bioavailable
Speaker 1: iron and pathogens, but you eat clay at the same time,
Speaker 1: the iron could also become bound by the clay and
Speaker 1: wouldn't be absorbed by your gut. Although the clay might
Speaker 1: be protecting you from pathogens to some extent, it's also
Speaker 1: preventing you from absorbing the nutrients. The fourth hypothesis for
Speaker 1: why people eat dirt or clay is that it might
Speaker 1: help with nausea, vomiting, and diarrhea by coding stomach. After all,
Speaker 1: a number of anti diarrheal treatments have kalin in them.
Speaker 1: Kalin puts the ko in chaopectate though the reasons for
Speaker 1: geophogy are still rather mysterious, Young stresses that it's far
Speaker 1: more common than we realize, partially because of those old
Speaker 1: stigmas against it. Young said, people don't like to talk
Speaker 1: about it or admit it. When I'm doing ethnographic interviews,
Speaker 1: I always ask how much earth do you eat? Instead
Speaker 1: of do you eat earth? Because so many people have
Speaker 1: sworn they don't eat it and later tell me that
Speaker 1: they do, but they lied because I didn't want you
Speaker 1: to think I was poor. Today's episode is based on
Speaker 1: the article why do people eat dirt? On how Stuff
Speaker 1: Works Up, written by Jesselyn Shields. Brain Stuff is a
Speaker 1: production of iHeartRadio in partnership with how Stuffworks dot Com
Speaker 1: and is produced by Tyler clang But four more podcasts
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