Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Titre : Improving iron nutrition from sorghum and millet based diets in malaria endemic areas

Auteur : Cercamondi, Colin Ivano

Etablissement de soutenance : Eidgenössische Technische Hochschule Zürich, ETHZ

Grade : Doctor of Sciences 2013

Présentation
Background Iron deficiency (ID) without or with anaemia (IDA) is a major global health problem affecting primarily vulnerable population groups such as children <5 years of age and women of reproductive age. In the semi-arid tropics, the aetiology of IDA is multifactorial, but the major factors are low dietary iron intake and bioavailability from monotonous diets based on staple crops, such as sorghum and millets, exacerbated by chronic parasitemia such as malaria infections. Iron fortification of staple foods is considered a promising approach to prevent and correct ID in certain population groups. ID in children <5 years of age, not yet consuming significant quantities of staple foods, can be prevented by commercially iron-fortified complementary foods or by complementary food supplements also called in-home fortification. A more recent approach to combat ID is iron biofortification which is the development of iron-enhanced staple crops by traditional plant breeding practices and/or genetic engineering. Sorghum and millets are important staple crops in areas of the semi-arid tropics where malaria is often endemic. Sorghum and millet foods are low in bioavailable iron and are particularly difficult to (bio)fortify with iron due to high concentrations of phytic acid (PA). In addition to PA, some sorghum and millet varieties contain considerable amounts of polyphenols (PPs) which, like PA, are known to inhibit iron absorption. The application of iron absorption enhancers, such as ascorbic acid (AA), ethylenediaminetetraacetic acid (EDTA) or enzymes degrading PA or PPs in sorghum and millet foods, potentially improves iron bioavailability from sorghum and millet foods. Malaria infections, which are known to interact with human iron homeostasis, must be considered when combatting ID in malaria endemic areas. Aim The overall aim of this thesis was to develop approaches to improve iron nutrition from sorghum and millet based diets in malaria endemic areas. This included an evaluation of the effect of asymptomatic malaria on iron absorption, an investigation into the effect of sorghum PPs on iron absorption and the optimization of iron absorption from a newly developed complementary food fortificant (CFF) added to a thin millet gruel. Moreover, iron bioavailability and total iron absorbed from an ironbiofortified pearl millet paste was compared with that from regular-iron and postharvest iron-fortified millet.

Mots clés : IRON DEFICIENCY DISEASES ; IRON ; MILLET ; NUTRITION OF WOMEN ; CHILDREN’S NUTRITION

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