Search

Pica, the urge to consume items generally not considered food, such as dirt, raw starch, and ice, are particularly common among pregnant women. However, the biology of pica in pregnancy is not well understood. Therefore, this study aimed to assess how pica relates to endocrine stress and immune biomarkers in a cohort of pregnant Latina women in Southern California. Thirty-four women completed a structured pica questionnaire. Maternal urinary cortisol and plasma cytokine levels were measured between 21 and 31 weeks' gestation. Associations between pica during pregnancy and biomarkers were assessed using linear regression models adjusting for gestational age. Twelve (35.3%) of the pregnant women reported pica (geophagy and amylophagy) during pregnancy. In multivariate models, those who engaged in pica had higher levels of cortisol (β: 0.37, 95% CI: 0.01, 0.073) and lower levels of IL-1β (β: -0.06, 95% CI: -0.11, -0.02), IL-8 (β: -0.30, 95% CI: -0.56, -0.05), IL-21 (β: -0.35, 95% CI: -0.63, -0.08), and type-1 inflammation composite (β: -0.29, 95% CI: -0.44, -0.14) than women who did not engage in pica. These results suggest that biological stress and immune response differ for women with pica compared to those without. This study suggests novel physiological covariates of pica during pregnancy. Further research is needed to better understand the mechanisms and temporality underlying the observed associations between pica and endocrine and immune biomarkers., (© 2023 The Authors. American Journal of Human Biology published by Wiley Periodicals LLC.)

Geophagy, the intentional consumption of soil, has been observed in humans and numerous other animal species. Geophagy has been posited to be adaptive, i.e., consumed soil protects against gastrointestinal distress and/or supplements micronutrients. We conducted a field experiment in the Budongo Forest, Uganda, to investigate geophagic behaviors, including soil preference, the quantity of soil eaten, and competition for access to preferred soils. We placed pairs of artificial tree stumps at two existing geophagy sites. One stump contained soil from the surrounding area, Sonso, that could supplement bioavailable iron. The other stump contained soil from a neighboring community, Waibira, that was richer in clay minerals, which could provide protection from plant secondary compounds. We monitored activity and engagement with the stumps for 10 days using camera traps. After 5 days, we reversed the type of soil that was in the stumps at both sites (i.e., a crossover design). Only Colobus guereza (black-and-white colobus monkeys) interacted with the stumps. These monkeys used visual and olfactory cues to select between the two soils and exclusively ate the clay-rich soil, consuming 9.67 kg of soil over 4.33 h. Our findings lend the greatest plausibility to the protection hypothesis. Additionally, monkeys competed for access to the stumps, and 13% of the videos captured aggression, including pushing, excluding, and chasing other individuals from the experimental stumps. Nine episodes of vigilance and flight behavior were also observed. Given that intentionally ingested soil is a valuable resource that may confer health benefits, geophagy sites should be conserved and protected.

Geophagy, the intentional consumption of earth materials, has been recorded in humans and other animals. It has been hypothesized that geophagy is an adaptive behavior, and that clay minerals commonly found in eaten soil can provide protection from toxins and/or supplement micronutrients. To test these hypotheses, we monitored chimpanzee geophagy using camera traps in four permanent sites at the Budongo Forest Reserve, Uganda, from October 2015-October 2016. We also collected plants, and soil chimpanzees were observed eating. We analyzed 10 plant and 45 soil samples to characterize geophagic behavior and geophagic soil and determine (1) whether micronutrients are available from the soil under physiological conditions and if iron is bioavailable, (2) the concentration of phenolic compounds in plants, and (3) if consumed soils are able to adsorb these phenolics. Chimpanzees ate soil and drank clay-infused water containing 1:1 and 2:1 clay minerals and > 30% sand. Under physiological conditions, the soils released calcium, iron, and magnesium. In vitro Caco-2 experiments found that five times more iron was bioavailable from three of four soil samples found at the base of trees. Plant samples contained approximately 60 μg/mg gallic acid equivalent. Soil from one site contained 10 times more 2:1 clay minerals, which were better at removing phenolics present in their diet. We suggest that geophagy may provide bioavailable iron and protection from phenolics, which have increased in plants over the last 20 years. In summary, geophagy within the Sonso community is multifunctional and may be an important self-medicative behavior.

Geophagy, the craving and purposive consumption of earth, is commonly reported during pregnancy. To date, most studies of geophagy have been cross-sectional and have not assessed its relationship with HIV infection. Therefore, to concurrently examine proposed etiologies of geophagy, a cohort of 371 women with mixed HIV status from Nyanza region, Kenya were recruited in late pregnancy and interviewed about pica at nine time points, through 21 months postpartum. Nutritional status (hemoglobin concentration and food insecurity), physical health (HIV infection and gastrointestinal distress), and psychosocial health (depression and perceived stress) were also repeatedly assessed. Prevalence of geophagy was greatest during pregnancy and decreased significantly postpartum. In a two-level hierarchical linear model, a one-unit increase in average hemoglobin (g/dL) was associated with a 35% decrease in the odds of geophagy. The adjusted odds ratios (CI) of geophagy were 3.98 (2.99, 5.29), 2.54 (1.13, 5.69), and 1.68 (1.15, 2.44) times higher if a woman was pregnant, reported diarrhea in the prior 24 hours, or was HIV positive, respectively. The adjusted odds ratio of geophagy was 1.61 (1.06, 2.45) times higher if a woman reported geophagy during childhood. Our results lend greatest plausibility to the protection hypothesis (i.e., that geophagy occurs in response to compromised immunity and/or infection). Given the high prevalence of geophagy, clinicians should regularly screen for the behavior and measure inflammatory biomarkers before treating geophagy with iron supplements, which can exacerbate some infections.

Background : Pica, the craving and purposeful consumption of nonfoods, is poorly understood. We described the prevalence of pica among women on Mfangano Island, Kenya, and examined sociodemographic and health correlates. Methods : Our cross-sectional study included 299 pregnant or postpartum women in 2012. We used a 24-h recall to assess pica, defined as consumption of earth (geophagy), charcoal/ash, or raw starches (amylophagy) and built multivariable logistic regression models to examine sociodemographic and health correlates of pica. Results : Eighty-one women (27.1%) engaged in pica in the previous 24 h, with 59.3% reporting amylophagy and 56.8% reporting geophagy, charcoal, and/or ash consumption. The most common substances consumed were raw cassava ( n = 30, 36.6%), odowa, a chalky, soft rock-like earth ( n = 21, 25.6%), and soil ( n = 17, 20.7%). Geophagy, charcoal, and/or ash consumption was negatively associated with breastfeeding (OR = 0.38, 95% CI: 0.18-0.81), and amylophagy was associated with pregnancy (OR = 4.31, 95% CI: 1.24-14.96). Pica was more common within one of six study regions (OR = 3.64, 95% CI: 1.39-9.51). We found no evidence of an association between food insecurity and pica. Conclusion : Pica was a common behavior among women, and the prevalence underscores the need to uncover its dietary, environmental, and cultural etiologies.

Objectives: Geophagy, the intentional consumption of earth, is widely practiced among humans and other mammals, but its causes are not well understood. Given the growing number of reports of geophagy among nonhuman primates (NHP), we sought to (1) advance and codify our understanding of the patterns and functional and evolutionary significance of geophagy among NHP and (2) provide a research agenda for a more unified approach to its study., Methods: We systematically reviewed all available literature on NHP geophagy, extracted available data on taxa, geography, climate, diet, sex, age-class, reproductive status, and the characteristics of the earth. We used these data to evaluate three major hypotheses about geophagy, that it is protective, provides mineral supplementation, and is nonadaptive., Results: We identified 287 accounts of geophagy among 136 species, adding 79 new primate species to the list of those considered in prior reviews. Nineteen percent of species were in the suborder Strepsirrhini, while 81% were in the suborder Haplorrhini. There were reports of geophagy from 9 of the 17 families and 39 of the 76 genera currently recognized by the International Union for Conservation of Nature., Discussion: The limited evidence suggests that geophagy is adaptive, and provides protection and mineral supplementation. We specify the behavioral, dietary, and soil data required to more rigorously investigate these hypotheses across representative species of all taxonomic groups, geographical regions, and dietary classification. Given the plausibility of geophagy for maintaining the health of both wild and captive populations, we urge further study and conservation of geophagy sites., (© 2018 American Association of Physical Anthropologists.)

Objectives: Geophagy is commonly reported by pregnant women and children, yet its causes and consequences remain poorly understood. Therefore, we sought to determine if geophagy could contribute micronutrients and/or be a source of heavy metal exposure by examining the elemental composition of earths consumed in Kakamega, Kenya., Methods: Ten samples of earths commonly consumed during pregnancy were collected by study enumerators and analyzed using inductively coupled plasma-atomic emission spectroscopy. Samples were either collected at markets or from walls of participants' homes, based on where participants reported most commonly sourcing their consumed earths., Results: Based on estimated intakes (40 g/day), all samples had lead levels that exceeded the provisional maximum tolerable daily intake, and one sample exceeded the threshold for arsenic. Further, estimated intakes of iron for all samples were at least 8.9 times higher than the established threshold. Elemental concentrations were also compared by the site of sample collection (market vs. household wall); market samples had significantly higher iron concentrations and lower calcium concentrations than wall samples., Conclusions: Geophagic earths in Kakamega may be harmful because of dangerously high levels of lead, arsenic, and iron. The prevalence of geophagy among vulnerable populations underscores the importance of understanding its causes and consequences for accurate public health messaging., (© 2018 Wiley Periodicals, Inc.)

Geophagy, the deliberate consumption of earth materials, is common among humans and animals. However, its etiology and function(s) remain poorly understood. The major hypotheses about its adaptive functions are the supplementation of essential elements and the protection against temporary and chronic gastrointestinal (GI) distress. Because much less work has been done on the protection hypothesis, we investigated whether soil eaten by baboons protected their GI tract from plant secondary metabolites (PSMs) and described best laboratory practices for doing so. We tested a soil that baboons eat/preferred, a soil that baboons never eat/non-preferred, and two clay minerals, montmorillonite a 2:1 clay and kaolinite a 1:1 clay. These were processed using a technique that simulated physiological digestion. The phytochemical concentration of 10 compounds representative of three biosynthetic classes of compounds found in the baboon diet was then assessed with and without earth materials using high-performance liquid chromatography with diode-array detection (HPLC-DAD). The preferred soil was white, contained 1% halite, 45% illite/mica, 14% kaolinite, and 0.8% sand; the non-preferred soil was pink, contained 1% goethite and 1% hematite but no halite, 40% illite/mica, 19% kaolinite, and 3% sand. Polar phenolics and alkaloids were generally adsorbed at levels 10× higher than less polar terpenes. In terms of PSM adsorption, the montmorillonite was more effective than the kaolinite, which was more effective than the non-preferred soil, which was more effective than the preferred soil. Our findings suggest that HPLC-DAD is best practice for the assessment of PSM adsorption of earth materials due to its reproducibility and accuracy. Further, soil selection was not based on adsorption of PSMs, but on other criteria such as color, mouth feel, and taste. However, the consumption of earth containing clay minerals could be an effective strategy for protecting the GI tract from PSMs.

Introduction: Anecdotal evidence suggests that pica occurs among Hispanic women in the United States, especially during pregnancy. However, the prevalence and socio-demographic and biological factors associated with pica in this population have not been adequately identified., Methods: Trained, bilingual study personnel conducted structured interviews at public health clinics in Salinas Valley, California with 187 pregnant Hispanic women in their 2nd or 3rd trimesters of pregnancy. Hemoglobin was measured using Hemocue; concentrations of transferrin receptor (TfR) and alpha-1 acid glycoprotein (AGP) were measured in dried blood spots. Multivariable stepwise regression analyses were conducted with pica during pregnancy as the dependent variable and individual- and family-level factors as independent variables to identify significant associations. Additionally, multivariable models were built to explore the associations between pica and iron status (iron deficiency and anemia)., Results: Half of all participants (51.3%) had ever engaged in pica, and 37.6% had done so during the current pregnancy. Pica substances included large quantities of ice, frost, raw starches, and various earthen items. Pica during the current pregnancy was significantly associated with higher TfR concentrations [OR: 1.29; 95% CI: 1.11, 1.51] indicative of low iron stores and greater food insecurity [OR: 1.20, 95% CI: 1.03, 1.40]. Women who engaged in pica during the current pregnancy were more likely to be iron deficient [adjusted OR: 2.58; 95% CI: 1.19, 5.60], but not anemic [adjusted OR: 1.40; 0.60, 3.23]., Conclusions: Among pregnant Hispanic women, pica was prevalent and strongly associated with iron deficiency and food insecurity. Clinicians should screen for pica during pregnancy in Hispanic populations, and future studies should elucidate the underlying etiology and consequences of engaging in pica during pregnancy., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Although pica, the craving and purposive consumption of non-food substances, is common among many populations, especially during pregnancy, the health consequences are not well understood. Further, very little is known about pica among Mexican populations in the United States and Mexico. Therefore, we conducted formative research to understand pica in this understudied population. Our objectives were to identify the frequency and types of pica behaviours, to understand perceived aetiologies and consequences of pica and to ascertain if the behaviour was common enough to warrant a larger study. We held nine focus group discussions (three in the Salinas Valley, California; six in Xoxocotla, Morelos, Mexico) with 76 Mexican-born women who were currently pregnant or had delivered within the past 2 years. Earth, adobe, bean stones and ice were the most commonly reported pica substances. Twenty-eight of the 76 participants (37%) reported ever engaging in pica; 22 participants (29%) reported doing so during pregnancy. The proportion of women reporting pica in the United States and Mexico was 43% and 34%, respectively. Women attributed pica to the overwhelming organoleptic appeal of pica substances (especially smell and texture) and to micronutrient deficiencies. Perceived consequences of unfulfilled pica cravings were birthmarks or fetal loss; fulfilled pica cravings were also thought to be generally harmful to the mother or child, with several women specifying toxic lead, pesticides or 'worms'. In sum, pica among Mexican women is common enough to warrant a larger epidemiologic study of its sociodemographic correlates and physiological consequences., (© 2014 John Wiley & Sons Ltd.)

Objectives: Pica is the craving for and consumption of nonfood items, including the ingestion of earth (geophagy), raw starch (amylophagy), and ice (pagophagy). Pica has long been associated with micronutrient deficiencies, but the strength of this relationship is unclear. We aimed to evaluate the association between pica behavior and the risk of being anemic or having low hemoglobin (Hb), hematocrit (Hct), or plasma zinc (Zn) concentrations., Methods: We systematically reviewed studies in which micronutrient levels were reported by pica status. We calculated the pooled odds ratio for anemia or weighted mean difference in Hb, Hct, or Zn concentrations between groups practicing or not practicing pica behaviors., Results: Forty-three studies including 6,407 individuals with pica behaviors and 10,277 controls were identified. Pica was associated with 2.35 times greater odds of anemia (95% CI: 1.94-2.85, P < 0.001), lower Hb concentration (-0.65 g/dl, 95% CI: -0.83 to -0.48 g/dl, P < 0.001), lower Hct concentration (-1.15%, 95% CI: -1.61 to -0.70%, P < 0.001), and lower Zn concentration (-34.3 μg/dl, 95% CI: -59.58 to -9.02 μg/dl, P = 0.008). Statistical significance persisted after excluding outliers and in subgroup analyses by pica type and life stage., Conclusion: Pica is significantly associated with increased risk for anemia and low Hb, Hct, and plasma Zn. Although the direction of the causal relationship between pica and micronutrient deficiency is unknown, the magnitude of these relationships is comparable to other well-recognized causes of micronutrient deficiencies. Pica warrants greater public health attention; specifically the potential physiological mechanisms underpinning the relationship between pica and micronutrient deficiencies merit further study., (© 2014 Wiley Periodicals, Inc.)

A relation between pica (the craving and purposive consumption of nonfood items) during pregnancy and anemia is observed frequently. However, few studies related pica behaviors to biomarkers of iron status, and little is known about pica prevalence in U.S. pregnant adolescents. To address this, we undertook a longitudinal study examining iron status and pica behaviors among a group of 158 pregnant adolescents (aged ≤18 y). Approximately two-thirds of the participants were African American and 25% were Hispanic. Maternal iron status indicators [hemoglobin, soluble transferrin receptor, serum ferritin (SF), total body iron (TBI), and serum hepcidin] were assessed during pregnancy (18.5-37.3 wk) and at delivery. Pica behavior was assessed up to 3 times across gestation. Among the 158 adolescents, 46% reported engaging in pica behavior. Substances ingested included ice (37%), starches (8%), powders (4%), and soap (3%). During pregnancy, mean SF [geometric mean: 13.6 μg/L (95% CI: 11.0, 17.0 μg/L)], TBI (mean ± SD: 2.5 ± 4.2 mg/kg), and hepcidin [geometric mean: 19.1 μg/L (95% CI: 16.3, 22.2 μg/L)] concentrations were significantly lower (P < 0.05) in the pica group (n = 72) than values observed among the non-pica group [SF, geometric mean: 21.1 μg/L (95% CI: 18.0, 25.0 μg/L); TBI, mean ± SD: 4.3 ± 3.5 mg/kg; hepcidin, geometric mean: 27.1 μg/L (95%: 23.1, 32.1 μg/L); n = 86]. Although additional studies must address the etiology of these relations, this practice should be screened for, given its association with low iron status and because many of the substances ingested may be harmful. This trial was registered at clinicaltrials.gov as NCT01019902., (© 2014 American Society for Nutrition.)

Pica, the craving and purposive consumption of non-food substances, is of public health concern for its potential deleterious and salubrious health consequences. However, neither its prevalence nor demographic correlates have been well characterized. Therefore, we conducted the first population-based study of pica and amylophagy in Madagascar. From February to December 2009, we surveyed pica and amylophagy behaviors in a random sample of 760 individuals >5 years in 167 households among two ethnic groups in 16 villages in the Makira Protected Area of Madagascar. Of the 760 individuals interviewed, 62.5% were children (5-11 years), 5.4% were adolescents (12-16 years), and 35.1% were adults (≥ 17 years). Thirteen non-food items were reported being consumed. Across the entire population in the prior year, the prevalence of geophagy was 53.4%, of amylophagy, 85.2%, and of other pica substances (e.g. charcoal, chalk) was 19.0%. The prevalence of these behaviors was not higher during pregnancy. These findings differ from previous studies in terms of the higher overall prevalence of these behaviors, the high prevalence among men, and the absence of any peak in behaviors during pregnancy. However, there are two categories of substances that elevate our estimates but fall outside the strict definition of pica as a craving: 1) substances consumed for self-medication and 2) substances viewed as food, such as all amylophagic substances in this case. Our results suggest that population-based studies of pica should include males of all ages. Further, the prevalence of the behavior underscores the importance of understanding the etiology and health consequences of these ingestive behaviors (Abstract S1).

Geophagy has been hypothesized to be an adaptive behavior, either as a means to allay nutrient deficiency or to protect against ingested pathogens and toxins. Others have proposed that geophagy is non-adaptive, occurring either to allay hunger or as an epiphenomenon of nutrient deficiencies. This paper evaluates these hypotheses using 482 published cultural-level accounts of human geophagy and 330 accounts of geophagy among 297 species of mammals, birds, and reptiles. Information was extracted from reports of human geophagy to permit statistical analysis; reports of non-human geophagy were tabulated. Human geophagy did not parallel changes in nutrient requirements, occurred most frequently among children and pregnant women and in tropical areas (where pathogen densities are highest), and was associated with ingestion of toxic substances and gastrointestinal distress. Earth ingested by humans was craved and carefully selected and prepared; it had high clay content, but few bioavailable mineral nutrients. In primates, geophagy was associated with both protection from toxins and obtaining nutrients, whereas in other vertebrates it was associated mainly with obtaining nutrients. Our results indicate that human geophagy is best explained as providing protection from dietary chemicals, parasites, and pathogens, whereas animal geophagy may involve both micronutrient acquisition and protection.

Pica, the purposive consumption of nonfood substances, is a millennia-old nutritional enigma. Its worldwide ubiquity, prevalence among pregnant women and children, and association with both positive and negative health outcomes, especially micronutrient deficiencies, underscore the importance of understanding this behavior. Multiple proposed etiologies of pica are reviewed, including cultural expectations, psychological stress, hunger, dyspepsia, micronutrient deficiencies (Fe, Zn, and Ca), and protection against toxins and pathogens. Currently available data, although limited, best support the protection hypothesis as a cause of most types of pica, although some evidence suggests that pagophagy (ice consumption) may occur during iron deficiency. It is possible that the binding capacity of pica substances explains the association with micronutrient deficiencies; earth, starch, etc. may render micronutrients in ingesta unavailable for absorption. Increased research efforts are warranted and must be hypothesis driven, interdisciplinary, and permit the testing of multiple causal inferences.

The etiology of pica, the purposive consumption of non-food substances, is not understood, despite its ubiquity among gravidae. We examined correlates of pica in a representative obstetric population (n = 2,368) on Pemba Island, Zanzibar, Tanzania to examine proposed etiologies. Cross-sectional data were collected on socioeconomic characteristics, food intake, geophagy (earth consumption), amylophagy (raw starch consumption), anthropometry, iron status, parasitic burden, and gastrointestinal morbidities. Amylophagy was reported by 36.3%, geophagy by 5.2%, and any pica by 40.1%. There was a strong additive relationship of geophagy and amylophagy with lower hemoglobin (Hb) concentration and iron deficiency anemia. By multivariate logistic regression, any pica was associated with Hb level (odds ratio [OR] = 0.76, 95% confidence interval [CI] = 0.72-0.81), nausea (OR = 1.45, 95% CI = 1.20-1.73), and abdominal pain (OR = 1.22, 95% CI = 1.01-1.48). These striking results indicate that the nature of the relationship between pica, pregnancy, gastrointestinal distress, and iron deficiency anemia merits further investigation.

The function of human geophagy has long been questioned. We sought to test hypotheses concerning its potential physiological effects through analysis of soils and patterns in geophagy behavior. Eleven samples of geophagic soils consumed by pregnant women on Pemba Island, Zanzibar, Tanzania, were characterized according to their color, texture, major element chemistry, trace element chemistry, bulk mineralogy, and clay mineralogy. An epidemiological study (N = 2367) and ethnographic interviews (N = 57) on Pemba yielded information about geophagic behaviors and socio-demographic and biological characteristics of those who consumed earth. The soils varied widely in color, ranging from light red to white through various shades of brown and yellow, and texture ranged from clay to sand. Major element chemistry of the soils also varied greatly; most were low in Fe and Ca. Trace elements, whether of biological or non-biological significance, were uniformly low when compared with normal ranges of mineral soils. The sole commonality among the samples is that all clay fractions were dominated by a kaolin mineral: kaolinite, halloysite, or a mixture of both. Geophagy behavior also varied greatly, with one major exception: a greater proportion of pregnant women (7.1%) and young children (4.5%) consumed earth than non-pregnant women (0.2%) or men (0%). The presence of kaolin mineral in all samples, its palliative and detoxifying properties, and the highest prevalence of geophagy among those most biologically vulnerable suggest that geophagy may be a protective behavior.

Background: Pica, the craving and subsequent consumption of non-food substances such as earth, charcoal, and raw starch, has been an enigma for more than 2000 years. Currently, there are little available data for testing major hypotheses about pica because of methodological limitations and lack of attention to the problem., Methodology: In this paper we critically review procedures and guidelines for interviews and sample collection that are appropriate for a wide variety of pica substances. In addition, we outline methodologies for the physical, mineralogical, and chemical characterization of these substances, with particular focus on geophagic soils and clays. Many of these methods are standard procedures in anthropological, soil, or nutritional sciences, but have rarely or never been applied to the study of pica., Principal Findings: Physical properties of geophagic materials including color, particle size distribution, consistency and dispersion/flocculation (coagulation) should be assessed by appropriate methods. Quantitative mineralogical analyses by X-ray diffraction should be made on bulk material as well as on separated clay fractions, and the various clay minerals should be characterized by a variety of supplementary tests. Concentrations of minerals should be determined using X-ray fluorescence for non-food substances and inductively coupled plasma-atomic emission spectroscopy for food-like substances. pH, salt content, cation exchange capacity, organic carbon content and labile forms of iron oxide should also be determined. Finally, analyses relating to biological interactions are recommended, including determination of the bioavailability of nutrients and other bioactive components from pica substances, as well as their detoxification capacities and parasitological profiles., Significance: This is the first review of appropriate methodologies for the study of human pica. The comprehensive and multi-disciplinary approach to the collection and analysis of pica substances detailed here is a necessary preliminary step to understanding the nutritional enigma of non-food consumption.

Geophagia may be harmful as a method for the transmission of geohelminths. In this study, we pose two questions in a representative sample of 970 pregnant women from Pemba Island, Zanzibar, Tanzania. Can consumed earth be a vector for geohelminth infection? And do geophagists have differential parasitic infection? The parasitological content of 59 non-food substance samples was analysed. Cross-sectional data regarding pica behaviour were collected through interviews conducted by local researchers. Ascaris, Trichuris and hookworm status was ascertained through Kato-Katz smears. The prevalence of geophagia at baseline was 5.6% and the overall prevalence of Ascaris, Trichuris and hookworm infection was 5.6%, 33.2% and 32.9%, respectively. No consumed soil samples contained infectious parasitic stages, and only one of the consumed pica substances (charcoal) contained parasites of potential risk to human health. In bivariate analyses, neither the prevalence nor the intensity of infection with Ascaris, Trichuris or hookworm differed significantly by geophagia status. Furthermore, in multivariate models, geophagia was not a significant predictor of helminth infection status. We conclude that geophagia is not a source of Trichuris or hookworm infection among pregnant women in Pemba (insufficient power to evaluate the effect of Ascaris), which is in contrast to existing findings of helminth infection and geophagia.

Although pica, the craving and purposive consumption of non-food substances, is common among many populations, especially during pregnancy, the health consequences are not well understood. Further, very little is known about pica among Mexican populations in the United States and Mexico. Therefore, we conducted formative research to understand pica in this understudied population. Our objectives were to identify the frequency and types of pica behaviours, to understand perceived aetiologies and consequences of pica and to ascertain if the behaviour was common enough to warrant a larger study. We held nine focus group discussions (three in the Salinas Valley, California; six in Xoxocotla, Morelos, Mexico) with 76 Mexican-born women who were currently pregnant or had delivered within the past 2 years. Earth, adobe, bean stones and ice were the most commonly reported pica substances. Twenty-eight of the 76 participants (37%) reported ever engaging in pica; 22 participants (29%) reported doing so during pregnancy. The proportion of women reporting pica in the United States and Mexico was 43% and 34%, respectively. Women attributed pica to the overwhelming organoleptic appeal of pica substances (especially smell and texture) and to micronutrient deficiencies. Perceived consequences of unfulfilled pica cravings were birthmarks or fetal loss; fulfilled pica cravings were also thought to be generally harmful to the mother or child, with several women specifying toxic lead, pesticides or 'worms'. In sum, pica among Mexican women is common enough to warrant a larger epidemiologic study of its sociodemographic correlates and physiological consequences.

The causes and consequences of geophagy, the craving and consumption of earth, remain enigmatic, despite its recognition as a behavior with public health implications. Iron deficiency has been proposed as both a cause and consequence of geophagy, but methodological limitations have precluded a decisive investigation into this relationship. Here we present a novel in vivo model for assessing the impact of geophagic earth on iron status: Gallus gallus (broiler chicken). For four weeks, animals were gavaged daily with varying dosages of geophagic material or pure clay mineral. Differences in haemoglobin (Hb) across treatment groups were assessed weekly and differences in liver ferritin, liver iron, and gene expression of the iron transporters divalent metal transporter 1 (DMT1), duodenal cytochrome B (DcytB) and ferroportin were assessed at the end of the study. Minimal impact on iron status indicators was observed in all non-control groups, suggesting dosing of geophagic materials may need refining in future studies. However, this model shows clear advantages over prior methods used both in vitro and in humans, and represents an important step in explaining the public health impact of geophagy on iron status. [ABSTRACT FROM AUTHOR]