Iron Absorption From Regular, Biofortified and Post-harvest Fortified Pearl Millet

Iron deficiency (ID) with or without anemia is still a main public health problem in sub-Saharan Africa and Southern Asia, especially in vulnerable population groups such as children below 5 years of age and women of reproductive age. The etiology of ID is multifactorial; but major causes are low iron dietary bioavailability and intake from monotonous cereal-based diets aggravated by chronic parasitic infections such as malaria and soil-transmitted helminthes. Approaches such as dietary diversification, supplementation with pharmacological iron doses, public health measures (e.g. deworming, malaria control) and food fortification with different iron compounds have notably reduced morbidity and mortality caused by ID but have not been universally successful. Biofortification is a new promising approach to combat micronutrient deficiencies such as ID. It is defined as the process of increasing the content and bioavailability of essential nutrients such as iron in crops by traditional plant breeding and/or genetic engineering. Pearl millet is a staple food for many people living in different areas of West Africa (e.g. Northern Benin) and India, two parts of the world, where ID is still widely prevalent. Therefore, pearl millet was one of the crops targeted for iron biofortification by HarvestPlus.

To improve human iron status successfully, the additional iron gained through biofortification has to be at least as bioavailable as the iron in regular peal millet varieties. For that reason we are planning an iron absorption study where we will investigate the iron bioavailability from an iron-biofortified millet variety and compare it with the iron bioavailability from a regular-iron millet variety and from regular-iron millet fortified post-harvest with ferrous sulfate (FeSO4). Iron absorption will be determined by incorporation of labeled iron into erythrocytes, at least 14 days after the administration of the test meals containing labeled iron (stable isotope technique). The three different test meals based on 1) regular-iron, 2) iron-biofortified and 3) post-harvest iron-fortified millet will be administered as multiple meals i.e. each study participant will consume each test meal for a period of 5 days (2 portions/day; one in the morning, one for lunch). Twenty apparently healthy Beninese women with a low/marginal iron status (serum ferritin < 25 ;g/L), non-anemic or mildly anemic (hemoglobin >90 g/L), 18-30 years of age with a body weight < 65 kg and normal body mass index will be included in the study.

The results of the study will provide important insights on the iron bioavailability from regular, biofortified and post-harvest fortified staple crops such as pearl millet when feeding multiple meals as part of a more complex diet. The results can be applied to different meals based on pearl millet such as the West African millet pastes or the Indian flat breads.