Strategies to Enhance Iron Absorption from Tef-injera in Young Women.

Objectives: Tef is a cereal indigenous to Ethiopia. The flour obtained is mostly used to produce a soft, pancake-like sourdough-bread, called injera. Since it contains considerable amounts of phytate, iron bioavailability from this Ethiopian staple is believed to be limited. We investigated different strategies to improve iron absorption from tef-injera. These included decreasing the phytate:iron molar ratio by simultaneously enhancing the iron content and lowering the phytate content during fermentation, by the addition of the enzyme phytase and by partially replacing tef by flours exhibiting high phytase activity. Additionally the impact of substituting FeSO4 by the alternative fortificant NaFeEDTA on bioavailability in humans was tested. Methods: Iron absorption was measured with stable isotopes in 2 groups of 17 young women in single-meal studies, serving modified tef-injera meals with tomato sauce in a cross-over design. Results: Iron absorption from traditional tef-injera was low (1.4%) and did not substantially increase with NaFeEDTA but approximately doubled (p<0.01) to 3.6% and 3.1% by reducing the phytate:iron molar ratio from 4.4 to 1.5 and 0.2 in variations with 10% wheat and purified phytase, respectively. Conclusions: Iron absorption was generally low from all meals and fortification of tef-injera with NaFeEDTA did not increase iron bioavailability compared to FeSO4, suggesting other factors, such as proteins or polyphenols, having an additional negative influence. Nevertheless, reducing the phytate content of tef-injera by either co-fortification with wheat or addition of purified phytase more than doubled iron bioavailability from this Ethiopian staple food and would provide additional absorbable iron.

Hookworm and S. haematobium infections, unlike Afebrile P. falciparum Malaria, do not Impair Intestinal Iron Absorption.

Objectives: In sub-Saharan Africa, parasitic diseases and low intake of bioavailable iron are the main causes of anemia. Anemia is further increased by inflammation during malarial infections blocking iron recycling and decreasing iron absorption. The influence of hookworm and Schistosoma infections on iron absorption and recycling is not known. Our objectives were to compare the influence of malaria, hookworm, and Schistosoma infections on inflammation, iron absorption and iron incorporation. Methods: Ivorian adolescents (12-17 years) presenting with a single infection of afebrile P. falciparum, hookworm or S. haematobium consumed 200 mL of test syrup containing 3 mg iron as ferrous sulfate labeled with 57Fe. Fractional absorption of the stable iron isotope was measured during infection and two weeks after treatment when subjects were free of infection. Erythrocyte incorporation of intravenous iron labeled with 58Fe and inflammation biomarkers were also measured. Results: Geometric mean iron absorption was 12.1% (95% CI: 9.2 - 18.0) during afebrile P. falciparum infection and increased to 23.6% (95% CI: 19.6 - 28.5) (P < 0.05) after treatment. Inflammation biomarkers were elevated during malarial infection and decreased after treatment. Light to moderate hookworm and S. haematobium infections did not increase inflammation and did not influence iron absorption (P > 0.05). Erythrocyte incorporation of intravenous iron was not affected by P. falciparum, hookworm or S. haematobium infections (P > 0.05). Conclusions: Unlike afebrile P. falciparum infection, light to moderate hookworm and S. haematobium infections do not lead to low-grade inflammation, and do not decrease iron absorption.