Iron Bioavailability In India: Historical Perspectives And Current Concerns
Nyhus, Christina Mayer
Indian women and children continue to suffer the highest rates of anemia in the world the despite economic and agricultural growth of the past four decades. High rates of iron deficiency anemia are attributed to low iron intakes and, perhaps more importantly, to low iron bioavailability from diets high in cereals and low in animal source foods. A better understanding of trends in iron deficiency risk in India over the past thirty is warranted and examined through intakes of dietary bioavailable iron. Adult 24-hour recall data from four cross-sectional survey rounds in 1975-80, 199697, 2000-01 and 2004-05 (n=45,026) were analyzed. A bioavailability algorithm was used to calculate dietary bioavailable iron (DBI) for each individual based on iron intake as well as intake of major iron inhibitors and enhancers, like phytates, tannins and ascorbic acid. Objectives of the research were to understand trends in DBI, to compare cereal-based diets in their ability to provide DBI and finally, the potential impact of iron-biofortified crops on improving DBI intakes. Results indicate that unlike iron intakes, which have remained unaltered from 1975-2000, DBI has improved, due to dietary shifts increasing iron bioavailability. However, trends indicate a drop in DBI in the last five years and parallel recent anemia findings. Analysis of specific cereal-based diets reveal that pearl millet and wheat diets are more protective against low DBI intake (less than 50% of basal requirements for iron) than rice based diets. Finally, iron biofortified rice and wheat have the potential to increase DBI intake levels to shift at least 4.5 million people out of iron deficiency. Findings indicate that the risk of iron deficiency has reduced over the past thirty years, with the exception of the last five years, and research on improving pearl millet production and/or continuing research on iron-biofortified rice could significantly reduce iron deficiency in India. Finally, this research highlights the need to examine iron intake at the level of bioavailable iron and that bioavailability algorithms, though they may require further refinement, are a useful tool for iron nutrition.
Dissertation or Thesis