Leila Larson is an Assistant Professor in the Department of Health Promotion, Education, and Behavior in the Arnold School of Public Health at the University of South Carolina. Dr. Larson’s work in the fields of nutrition and global health has three foci: 1) developing and evaluating integrated interventions to improve early child development and child health in resource-limited settings, 2) understanding the intersection of prenatal and postnatal exposures (e.g., climate change, malnutrition, infection, and microbial dysbiosis) on maternal and child health and development, and 3) improving the measurement of nutritional biomarkers and diagnosis of nutritional deficiencies in population surveys. She has worked on several nutrition trials in pregnancy and childhood in countries such as Liberia, India, Bangladesh, and Malawi. Dr. Larson has a PhD in Nutrition and Health Sciences from Emory University, USA and a MPH in Environmental Health from Columbia University, USA. Click here for synopsis of Dr. Larson’s project.
Sera Young is Professor of Anthropology and a Morton O. Schapiro Faculty Fellow at the Institute for Policy Research. She has dedicated her career to understanding how women, especially in low-resource settings, cope to preserve their health and that of their families. Professor Young’s current research is focused on quantifying human experiences with problems with water, and unpacking their consequences for nutrition, health, and well-being. To that end, she led a large team in the development of the Water InSecurity Experiences (WISE) Scales, the first cross-country equivalent way of measuring water access and use. She has co-authored more than 170 peer-reviewed publications and been funded by many international agencies; awards include the Margaret Mead Award for her book Craving Earth, an Andrew Carnegie Fellowship, and a Leverhulme Visiting Professorship. Click here for Dr. Young’s PowerPoint about pica. Social media: @profserayoung.
In this podcast, Drs. Larson and Young talk with Helen Osborne about:
- Different types of pica
- Prevalence of pica in different populations
- Relationship between pica and iron deficiency anemia
- Theories about what causes pica
Producer and audio editor: Adam Weiss, Relativistic Media
Transcript:
HELEN: Welcome to Talking About Blood. I’m Helen Osborne, host of this podcast series and a member of the advisory board for The Blood Project. I also produce and host my own podcast series about health communication, and it’s called Health Literacy Out Loud. Today I’m talking with two guests. Dr. Leila Larson is an assistant professor in the Department of Public Health Promotion, Education, and Behavior at the Arnold School of Public Health at the University of South Carolina. Laila’s work focuses on nutrition and global health. This includes research in Liberia, India, Bangladesh, and Malawi about nutrition in pregnancy and childhood. Dr. Sera Young is professor of anthropology at Northwestern University in Chicago. Her ongoing focus is understanding how women, especially women in low-resource settings, cope to preserve their health and that of their families. Among Sera’s many accomplishments, she is author of the award-winning book Craving Earth and has co-authored over 170 peer-reviewed publications. Welcome to you both.
SERA: Thanks, Helen. It’s amazing to be here.
LEILA: Thank you for the invitation. Glad to be here, Helen.
HELEN: Well, the invitation started with Dr. Bill Aird, who heads up The Blood Project. He had just finished reading Sera’s book called Craving Earth about something called pica. And I’m looking at the subtitle of what pica is, the urge to eat clay and starch and ice and chalk. Bill is a hematologist and found this absolutely fascinating information and relevant to what he does in all his work about blood. He saw a lot of connections there. So I’m glad we had this opportunity to talk about those connections together, about pica and issues related to blood. So let’s start from the beginning. What is pica?
SERA: Pica, P-I-C-A, refers to craving and consumption of any item that is typically not considered food. So, like you said, it could be earth, but many people crave many different non-food items.
HELEN: So pica is that overall term, craving non-food items. Leila, how would this possibly relate to blood?
LEILA: Right. So we often think of pica being caused by anemia or nutritional deficiencies. More deficiencies of iron, but it can also be due to deficiencies in zinc and deficiencies in calcium. But really, we think of pica as being caused by anemia.
HELEN: Okay. So pica is caused by anemia in there, or there’s correlation of some sort. And both of you have done your research in Africa and other parts of the world there. Tell us more about how you first learned about pica and what it is like in a person’s life.
SERA: I would be glad to. So I’m going to take you back 20 years when I was a baby baby. I was a master’s student in medical anthropology doing fieldwork in Zanzibar, Tanzania. And a professor of nutrition, Rebecca Stoltzfus, had asked me to do an ethnography of anemia during pregnancy. And what that means is to understand how people think about anemia, what they do to treat anemia, what they think causes anemia. And I was sitting in the backyard with a woman asking her what she thought caused anemia. And she grabbed sort of this parcel of earth stashed next to her. And she said, oh, this, this is what causes anemia, is eating this earth.
HELEN: Eating the earth. And she didn’t just like scoop down from the ground. It wasn’t just the nearest piece of dirt by her foot. It was particular dirt?
SERA: It was absolutely very particular dirt. People talk about craving very particular earth. On the cover of my book, you can see a woman in Zanzibar holding earth. And this is earth that we walked for like 45 minutes into the rainforest to get. There’s many, many flavors of earth, many, many types of earth. People like to eat very clay-rich earth that’s clean.
HELEN: Is that all that there is to pica, or is that just kind of a component of pica is craving this earth?
SERA: Leila’s seen a few different types of pica in her work. Maybe you want to tell us about that, Leila.
LEILA: Yeah, this is actually how I came into pica. I mean, I had heard Sera, Dr. Young talk about pica at various points of when I was doing my dissertation, and it really piqued my interest. And when I started working in Malawi on a trial of iron supplementation, we got in touch with Sera because we thought this would be such a nice opportunity to be looking at pica and what is its relationship with iron in this very rigorous approach. So we did. Sera urged us to add this survey to our trial, and we found some really interesting results. So essentially, let me give you a bit of context. So in Malawi, there’s quite a bit of anemia. We often think of anemia as being related to pica, as I was saying earlier. But we know that basically women who engage in pica, particularly geophagy, which is the consumption of earth, are often more likely to be anemic, and they’re often more likely to be iron deficient. But rigorous evidence linking those nutritional deficiencies as a cause of pica is lacking. So what we did was, as part of this randomized trial in Malawi of intravenous iron in anemic pregnant women, we randomized over 800 anemic pregnant women in their second trimester to receive either, it’s called ferric carboxymaltose, which is basically just intravenous, a single dose of intravenous iron. And then the other half of women received standard of care.
HELEN: They were still getting iron?
LEILA: We called it standard of care oral iron. So they were basically sent home with what is the standard of care, which is iron pills.
SERA: Daily tablets, right?
LEILA: Yes
SERA: To be taken daily
LEILA: Ultimately, the decision to take these pills was up to the women. What often, I will say, what often happens in places like Malawi, and even in the US, is that because of the side effects that happen from these oral iron tablets, many women end up not taking the oral iron. So half the women are getting this single dose intravenous iron, half are getting sent home with iron pills. It’s up to them whether or not they take them. And we assess pica at baseline, so before any treatment, and then four weeks later. What we found is really interesting. So at baseline, so these are all anemic pregnant women in their second trimester. We found that 71% of them had pica. So that’s quite a high percentage.
HELEN: So wait, let me just go a little slower here. I’m not a scientist myself, and you know, we might have other listeners too. You were looking at women in Malawi in their second trimester. They all are iron deficient anemic, and they all have cravings for earth. Is that correct?
LEILA: Not exactly, but almost. So all women…
HELEN: I told you I’m not a scientist, okay.
LEILA: That is okay. Let me try and simplify it. All the women who were enrolled, who were participating, were anemic. Some anemia is caused by iron deficiency, but other anemia could be caused by other things. So we know that there’s other deficiencies that cause anemia, but largely, yes. Largely, most of anemia is caused by iron deficiency. So all these women were anemic. They were in their second trimester of pregnancy, but that’s it. And then we assessed pica in all of them. So we asked them questions to see whether they engaged in pica. And we found that 71% of them did engage in pica. So they either consumed earth, they consumed raw starch, or they consumed ice.
HELEN: 71%!
SERA: And I just want to give a little context to that, which is 71% prevalence during pregnancy is not at all unheard of. And we’ve seen really high prevalence of non-food cravings, especially during pregnancy, especially in tropical climates.
HELEN: I was going to ask about the location of it. I’ve had kids too. I certainly didn’t recall any particular kind of cravings, and certainly not something that would be a non-food item. Is this mainly in other parts of the world and not in the U.S., this pica craving?
SERA: So there’s been some great studies of pica cravings here in the U.S. And in the 50s and 60s, it was observed really quite regularly among Black women, especially in the southern United States. Kimberly O’Brien, a professor at Cornell, did a study amongst pregnant adolescents in and around Syracuse, upstate New York. I can’t remember the prevalence offhand, but it was maybe something like 30%.
LEILA: It was 38.
SERA: Oh, okay. Hello. Nice
HELEN: So this is women who were pregnant in the United States in upstate New York.
LEILA: Yes. And Sera, Dr. Young was also involved in a study in California, right, in Hispanic women.\
SERA: Oh, that’s right.
LEILA: And they found that, so these are Hispanic pregnant women in California. They found 51% of them engaging in pica. So yes, it’s seen everywhere. But I will say it’s more common and less stigmatized in places like sub-Saharan Africa, where we found over 70% of women engaging in pica.
HELEN: So before we get to the end result of your research, which we will get to, my friends and I, we’re all having babies around the same time. I never heard anyone talk about this. Do you think that they did engage in pica and just didn’t talk about it? Or do you think that they didn’t and it’s more the populations you were specifically mentioning?
SERA: Not to get scientific, but I’m going to talk about this concept called effect modification. And what all that means really is that there is a likelihood, a greater likelihood to want to eat non-food things when you’re pregnant. However, our cultural expectations in our environment and what we saw our aunties do growing up and a whole bunch of things make us more likely to admit to doing this or to suppress doing it.
HELEN: Oh, okay.
SERA: It’s kind of like, I don’t know, picking your nose. Most people have an urge to do it. Most of us do it, but we won’t all admit it. I find this very similar and there’s a much more likely to do it if you’re under certain circumstances, like in a place with a lot of pathogens in the environment.
HELEN: Okay.
SERA: But you’re also more likely to admit it.
HELEN: It’s really interesting. It’s also interesting talking with both of you. Sera, you’re an anthropologist. Layla, you are a researcher there. So you’re going at it more the numbers way and the cultural way, it sounds like.
SERA: I don’t know if that difference is so important. I’m actually trained as a nutritionist and I’ve done a lot of epidemiological studies too.
HELEN: So get to the end of your research, Leila. What are you learning by doing this with these women in Malawi?
LEILA: Like I was saying, we see that over 70% of the women in this trial are engaging in pica. Those who consume earth, now that’s important. So 32% of the women in this trial craved and consumed earth. What we found was that the prevalence of geophagy in particular, so the consumption of earth, decreased more among women who were assigned to the IV iron compared to those who were assigned to the standard of care. And this reduction in geophagy, so the consumption of earth, was accompanied by very large reductions in both iron deficiency and in anemia. And so we’re seeing this concurrent sort of decreases in geophagy in those who receive the IV iron compared to the standard of care, concurrent with decreases in iron deficiency and anemia. So what it’s telling us is that geophagy is reduced by improvements in iron status and anemia during pregnancy.
SERA: And Leila, what about all the other types of pica that people had? Did those change?
LEILA: Thank you for bringing that up. Those did not change.
HELEN: And what other kinds of pica?
LEILA: We haven’t talked about these so much, but raw starch, so craving and consuming raw starch. So things like raw rice, we saw quite high prevalence of that in our participating women, but the prevalence of consumption of raw starch did not change from the IV iron, nor did the consumption of ice. And I will say, this is not just a little bit of ice, it’s bags and bags of ice. But in places like Malawi, and we were in both urban and rural Malawi, we had one site in rural Malawi and one site in urban Malawi, the consumption of ice was pretty low just because of the context. But, you know, in the U.S. we see higher prevalence of large… In the U.S. people eat party bags full of ice per day.
HELEN: Really?
SERA: They eat boxes of cornstarch per day, and each box of cornstarch has like 1,200 calories in it. So there’s like completely empty calories, and you can find YouTube videos of people eating all of this stuff.
HELEN: This is fascinating, putting it all together. So let me tell you about the listeners of Talking About Blood. So they may be seasoned hematologists like Bill Aird is, physicians who’ve been in practice a long time, just want to keep learning more, or maybe they see someone in their practice who would be helpful for. Another large group on this podcast of the listeners are people early in their careers, whether they’re going into medical school or in their residency, or they’re going into some of the sciences. And then we also have people like me, who are just so curious about anything having to do with blood. From all the work both of you are doing and all you’re learning, what would you want each of those groups to know?
SERA: Yeah, I have maybe two messages.
HELEN: Okay, Sera, take it.
SERA: Yeah, and the first is that pica is a behavior that’s found worldwide, and it’s consistently underestimated, often because people don’t talk about it. So when you are seeing anemia, and it’s some unidentified etiology, I would highly recommend asking which non-food cravings they have. Not if they have them, but which ones do they have? That normalizes it a bit.
HELEN: Interesting. So you would just be saying to the patient you’re with, and you’re trying to understand this anemia a little more, like, which cravings?
SERA: Which non-food cravings do you have?
HELEN: Okay.
SERA: We’ve also authored some clinical guidelines in Up to Date, which is a handbook for physicians where we talk about specific recommendations for what to do when you are seeing a patient present with this. My third point would be, while anemia and pica often go hand-in-hand, we still don’t understand the causal relationships. It is possible that maybe people are getting some iron from some of these substances that they’re craving, so it’s like a solution. But it’s also possible that earth, especially clay, is really good at binding iron and other micronutrients we consume, and could be exacerbating or making worse the micronutrient deficiency, including anemia.
HELEN: Oh, isn’t that interesting? So it could be both a cause and a solution.
SERA: Yeah. And I’ll just wrap this up, not with advice, but just a piece of information, which is that a lot of these substances that are craved are dry, powdery substances that are good at binding with pathogens. We know diarrhea is palliated, is made better with clay. It can treat nausea, and it can actually treat the cause of the gastrointestinal distress. So we see that maybe this is palliative in some cases, but ice is way out there. It’s a mystery that begs to be solved, and I hope your viewers hop on board this mysterious train to help understand why women are having, especially women, not only women, are having these cravings.
HELEN: Leila, what else would you want this audience to know? We talked a little bit about the clinical side, but you also learned a lot about the supplementing with the iron. What have you learned that others would want to know?
LEILA: I’m going to jump on board with the, I think this is such an interesting and really complex phenomenon, and I personally would love to continue the research around, this research around pica, not just in sub-Saharan Africa, but also in places like the United States, where I think, you know, as Dr. Young was saying, it’s underreported and it’s underdiagnosed, but I think that it is actually quite prevalent. When I talk to friends, family, when I talk to colleagues and even clinicians about pica, it seems that everybody knows at least one person or knows somebody who knows someone who engages in pica. So I just, I think it’s everywhere. I think it’s very interesting. I hope that my own research can really help to destigmatize it and find some solutions.
HELEN: I want to get also to the newer scientists, the one, the person maybe entering into science. Both of you have perhaps gone in nontraditional paths somewhat to get to the point that you’re at, and now you’ve met each other. What would your recommendations be, and I don’t know your backstories particularly of how you got to where you are now, but what would you recommend to someone new in their career to come up with an under-researched topic like this?
LEILA: I had a very circuitous route to where I am now. I think what I would say is, you know, don’t be afraid to follow what brings you joy, brings you passion. If you wake up every morning and you are not happy with what you are doing, I suggest thinking about what brings you joy and following that. That is something I’ve done personally.
HELEN: Wait, wait, wait. You didn’t wake up in the morning going, I think I want to really research pica because it’ll give me joy, did you?
LEILA: Not entirely pica, but I was working for the mining industry when I decided to change into public health.
HELEN: Oh, interesting. Okay. And I’ve gotten to know you a little bit in our planning, and you were doing this with such enthusiasm and glee. It’s amazing.
LEILA: Yeah. I mean, the other thing I would say is find people, find kind, fun people that you love working with, and I think that’s how Sera and I found each other. We have so much fun together, and I think that’s why, partly why, we are working together on pica now.
HELEN: So what about the people like me who, this is all new, and I’m telling people I’m doing a podcast on something called Pica and People Eating Earth, and they’re going, what? What? What would you want the general public to know? How do they respond when you tell them what you are working on?
LEILA: I think they’re all very interested. Like I said, I think when I bring up Pica, a lot of people say, oh, I know somebody, and they have so many stories to tell. So I think it’s something that is sort of in the mainstream that a lot of people find very interesting.
SERA: My advice is a life lesson, maybe if we’re professors or not, we could all, we should all do, which is listen to women. So I got this idea by listening to women. I was asking what, you know, I was going around in Zanzibar saying, why are you doing this? Why are you doing this? And this woman said, I don’t know, why don’t you tell us? The same thing happened with what brought me to water, is listening to what women needed and wanted, and we need to be listening to women all the time. They have good ideas.
LEILA: Amen.
HELEN: Oh, what a wonderful place to put this conversation, listening to both of you, our listeners are listening to all of you and learning a lot. Just before we put a pause in this conversation, I want to ask about the babies. So you were studying women before they gave birth. What was the health of their babies? If they engaged in pica, if they engaged in particular kinds of pica, whether they ate earth or not, or whether they took the iron, what outcomes did that have on the next generation?
SERA: I don’t know the results of Dr. Larson’s study, but I will say in general, women who are anemic have a harder time in labor, and they have a harder time after labor for a variety of reasons. It’s harder to breastfeed. It’s harder to have the energy to care for those babies. Pica in and of itself is not harmful per se. A little bit of earth per day, if it doesn’t have contaminants like lead in it, is fine. Most forms of pica will not harm the woman or the child.
HELEN: Thank you. You found the same thing, Leila?
LEILA: We have actually not looked at the associations between pica and child outcomes, but that is something that we would like to do in the future. I will say that those who received the IV iron had lower anemia and iron deficiency throughout pregnancy and later, but there were no effects on the children themselves.
SERA: So unfortunately, your readers won’t be able to see this photo, but I’m going to show you a picture of a little baby sitting on a mat. And this is a, well, she’s like a year old. And this, I was interviewing a woman a year after I had interviewed her during pregnancy. And I said, hi mama, you know, have you thought any more about pica and what do you think caused your cravings? And she pointed at this like innocent little baby sitting here. She pointed vehemently at this baby and said, that baby caused me pica. That’s the cause of my pica. Because when he left me, my cravings ended.
HELEN: Interesting. Okay. I would recommend for all the listeners who want to learn more, get a copy of your book, Craving Earth by Sera Young. It’s fascinating and written in a very, very conversational manner. You don’t have to be, you know, have to have a PhD to be able to understand it. Both of you, you are listening, you are sharing, listen to women, take these opportunities, see what brings you joy. Thank you both so much for being guests on Talking About Blood.
LEILA: Thank you for having us.
SERA: Always a pleasure to talk about pica.
HELEN: As we just heard from Layla Larson and Sera Young, it’s important to put many of these different components together, such as iron deficiency, anemia, and pica. And you keep learning and listening about that. To learn more about The Blood Project and explore its many resources for professionals and trainees and patients, go to thebloodproject.com. I invite you to also listen to my podcast series about health communication at healthliteracyoutloud.com. Please help spread the word about this podcast series and The Blood Project. Thank you for listening. Until next time, I’m Helen Osborne.