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ARS Home » Northeast Area » Ithaca, New York » Robert W. Holley Center for Agriculture & Health » Plant, Soil and Nutrition Research » Research » Publications at this Location » Publication #333332

Research Project: Bioavailability of Iron, Zinc and Select Phytochemicals for Improved Health

Location: Plant, Soil and Nutrition Research

Title: A novel in vivo model for assessing the impact of geophagic earth on iron status

Author
item SIEM, GRETCHEN - Cornell University - New York
item Tako, Elad
item AHN, CEDRIC - Cornell University - New York
item BODIS, MARY - Cornell University - New York
item Glahn, Raymond
item YOUNG, SERA - Cornell University - New York

Submitted to: Nutrients
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/2/2016
Publication Date: 6/13/2016
Citation: Siem, G., Tako, E.N., Ahn, C., Bodis, M., Glahn, R.P., Young, S. 2016. A novel in vivo model for assessing the impact of geophagic earth on iron status. Nutrients. 8(6):E362. doi:10.3390/nu8060362.

Interpretive Summary: The causes and consequences of geophagy, the craving and consumption of earth, remain unclear, 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 (animal) model for assessing the impact of geophagic earth on iron status: Gallus (broiler chicken). For four weeks, animals were gavaged (oral administration) daily with varying concentrations of geophagic material or pure clay mineral. Differences in Hemoglobin (indicator of iron status) across treatment groups were assessed weekly and differences in liver ferritin, liver iron, and gene expression of the iron transporters DMT-1 (intestinal iron transporter), DcytB (iron reductase) and ferroportin (iron transporter) were assessed at the end of the study. Although dosing of geophagic materials will need refining in future studies, this model shows clear advantages over prior methods used both in vitro (call culture) and in humans, and represents an important step in explaining the public health impact of geophagy on iron status.

Technical Abstract: 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 concentrations of geophagic material or pure clay mineral. Differences in Hb across treatment groups were assessed weekly and differences in liver ferritin, liver iron, and gene expression of the iron transporters DMT-1, DcytB and ferroportin were assessed at the end of the study. Although dosing of geophagic materials will need refining in future studies, 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.