Adequacy of Iron and Zinc Contents and Estimated Bioavailability in Commercially Available Complementary Foods in Ethiopia

Abstract

Objectives: Evaluate the adequacy of iron and zinc contents and estimated bioavailability of complementary foods (CFs) processed in Ethiopia. Methods: Seven locally-produced fortified and non-fortified cereal-based CFs were purchased from supermarkets in Addis Ababa, Ethiopia. Iron and zinc contents were determined by atomic absorption spectrometry and results were compared with recommendations for fortified CFs. Phytate particularly myo-inositol hexaphosphate (IP6) was determined using high-performance anion-exchange chromatography. Iron and zinc bioavailability was estimated by calculating IP6-to-mineral molar ratios. Results: Iron and zinc contents of CFs were in the range of 5.85-22.31 and 0.80-12.07 mg/100g DM, respectively. The contribution to iron and zinc requirement assuming a daily intake of CF equal to the recommendations  (i.e. 40 and 60 g for the 6-11 and the 12-23 month-old children, respectively) was 21-81% and 6-97% for 6-11 months and 50-100% and 10-100% for 12-23 month-old children respectively. With IP6 content in the range of 235-893 mg / 100 g DM, the molar ratios of [IP6]:[Fe](0.89-7.07) and [IP6]:[Zn] (1.93-30.63) were above the recommendations for most CFs analyzed. Conclusions: All CFs analyzed had iron content below the recommendation for 6-11 month-old children but 5 out-of 7 CFs contained adequate iron for 12-23 month-old children. Regarding zinc, only 2 out-of 7 CFs could contribute to more than 80% of the requirement for both age groups. Mineral-to-phytate molar ratios also predicted low bioavailability. Therefore, manufacturers need to consult nutritionists to define proper fortification of processed CFs and for further modification of their processing methods to improve mineral bioavailability, so that children meet their daily nutrient requirements.