Nuclear Techniques Can Help to Identify Strategies to Prevent Micronutrient Deficiencies in Young Children
Preparing amaranth enriched tortillas in Guatemala (Photo courtesy of J.T. Rodríguez)
Cooking of kale and adding peanut butter increases the vitamin A value of kale (Photo courtesy of A.H. Siwela)
Eight delegates from Bangladesh, Guatemala, India, Mexico, Netherlands, USA, Zambia and Zimbabwe gathered at IAEA Headquarters in Vienna, from 7-9 March, to discuss the coordinated research project "Using Nuclear Techniques to Develop and Evaluate Food-Based Strategies to Prevent Micronutrient Deficiencies in Young Children." The main aim of the meeting was to review the results generated during the project and recommend new strategies for enhanced micronutrient intake in infants and young children, in low-resource settings.
One of the studies examined iron absorption from amaranth enriched tortillas compared to traditional maize tortillas in Guatemalan toddlers. Preliminary results indicate that total absorbed iron was significantly higher from the amaranth enriched tortillas. Amaranth, therefore, seems to be a promising strategy for use as a complementary food in an effort to increase iron intake in young children. Another study in Zimbabwe examined the vitamin A value (i.e., bioconversion efficiency of provitamin A to vitamin A) of kale, a green leafy vegetable, when prepared and consumed with lard or peanut butter (rich in protein and vitamin E). Results indicate that the addition of fat to processed kale (cooked and pureed) significantly enhanced the bioconversion to vitamin A in preschool children. Kale, therefore, should be promoted as part of a dietary diversification strategy to complement vitamin A intake from other sources.
Adequate nutrition during infancy and early childhood is fundamental to the development of each child's full human potential. The period from birth to two years of age is a "critical window" for the promotion of optimal growth, health and behavioural development. In resource-poor households in low-income countries traditional complementary foods are predominantly plant-based and generally provide insufficient amounts of certain key nutrients (particularly iron, zinc and vitamin A) to meet the recommended nutrient intakes during the age range of 6-24 months. The foods used are often monotonous with emphasis on unrefined cereals or legumes that contain high amounts of phytic acid and phenolic compounds and with negligible quantities of animal source foods, and fruits and vegetables rich in vitamin C, vitamin A and provitamin A. As a result, these home prepared complementary foods often have low nutrient density and low bioavailability of trace elements, especially of iron and zinc.
The IAEA started this coordinated research project (CRP) in 2011, undertaking studies aimed at assessing strategies to improve the bioavailability of zinc and iron in modified complementary foods. The studies also considered strategies to prevent vitamin A deficiencies by evaluating the vitamin A value of plant foods and the effect of foods rich in provitamin A on vitamin A intake and status. To do so, stable isotopes of iron and zinc as well as stable isotope-labelled provitamin A were used to measure their bioavailability from improved complementary foods and bioconversion from provitamin A to vitamin A respectively. Furthermore, total body vitamin A pool size was estimated using stable isotope-labelled vitamin A.
All in all the CRP is a success, providing evidence-based results to recommend new strategies for dietary modifications to enhance the micronutrient intake of vitamin A, zinc and iron from plant-based local foods and human milk to improve infant and young child feeding practices. These recommendations will be passed on to programme planners and policy makers once their efficacy has been confirmed to improve micronutrient nutrition in low-resource settings. The CRP furthermore contributed to building human resources, technical skills and collaboration between participating research entities. Some studies within the CRP are still ongoing and will be completed shortly.