Evaluation of Low Dietary Iron as a Nutritional Adaptation to Infectious Disease

University Of Washington, Seattle WA

Investigators

Abstract

Anemia affects an estimated 700 million people worldwide. In most cases it is regarded as a disorder arising from inadequate dietary iron that requires treatment with supplementation. In recent years, however, research has demonstrated that low circulating iron levels can arise from a well-regulated non-specific immunological defense against infection, the iron withholding response. This response protects a human host by sequestering iron needed by microorganisms for growth. The research proposed here will investigate whether low circulating iron from low dietary intake similarly protects the host from infection in a high disease load environment. Specifically, this research will weigh the potential protective benefits of moderate iron deficiency against the possible adverse consequences, particularly in relation to the specific immune response. This study will investigate the effect of iron deficiency on one aspect of the specific immune response, cell-mediated immunity, using blood spots collected on filter paper from 314 Kenyan children. The investigators will refine an assay for serum transferring receptor, a marker that is currently considered the gold standard for assessing iron status. Commercial assay kits that are designed to be used with venous blood samples will be modified for use on dried capillary blood spots, resulting in an easy, minimally invasive, "field-friendly" method that will also be useful for future community-based assessments. The results of this study will contribute to a broader understanding of the functional tradeoffs of mild iron deficiency and the nutritional ecology of disease resistance.