Prevention and control of micronutrient deficiencies in developing countries: current perspectives

Despite strategies employed to tackle micronutrient malnutrition, limited progress has been achieved in the developing countries. Of global concern are deficiencies in iron, vitamin A, zinc, folate, and iodine. This review aims to explore up-to-date scientific evidence on the effect of different micronutrient strategies on biomarkers and health outcomes, and for each strategy, to highlight strengths, limitations, and factors contributing to success or failure. PubMed/MEDLINE and EBSCO databases and Google-indexed scientific literature were searched for relevant articles and documents, limited to human studies reported since 2003. Evidence shows that the most cost-effective approaches to address symptoms of micronutrient malnutrition are targeted supplementation and/or fortification with iron, iodine, zinc, folic acid, vitamin A, and multimicronutrients, provided that households have access to primary health care and that there is consistent long-term coverage, monitoring, adequate marketing, and commercial commitment. Dietary diversification/modification interventions are probably the most sustainable strategies to address causes of deficiency, but permanent solutions are still required in controlling micronutrient malnutrition at both research and public health levels. Furthermore, many scientific gaps remain, hindering the development of robust public health guidance. These gaps are due to the paucity of well-designed community-based studies, lack of information on biological mechanisms behind relationships between micronutrients and outcomes, and inconsistent results. Further adequately powered long-term trials are needed to fill these gaps. Lessons learned from large-scale nutritional programs suggest that, for long-term improvements in nutrition and health, dietary strategies must integrate agricultural production with primary health care and female nutrition education and empowerment. They must also promote behaviors that support adequate intake, ensure availability of supply, and help to empower communities to become more self-reliant.