Introduction

Zinc deficiency is one of the ten biggest factors contributing to burden of disease in developing countries with high mortality.1 Since the problem was highlighted in the World Health Report 2002, calls have increased for supplementation and food fortification programmes.2 3 Zinc interventions are among those proposed to help reduce child deaths globally by 63%.4 Populations in South East Asia and sub-Saharan Africa are at greatest risk of zinc deficiency; zinc intakes are inadequate for about a third of the population and stunting affects 40% of preschool children.5 Zinc is commonly the most deficient nutrient in complementary food mixtures fed to infants during weaning.6

Improving zinc intakes through dietary improvements is a complex task that requires considerable time and effort.7 The case for promoting the use of zinc supplements and for fortifying foods with zinc, especially those foods commonly eaten by young children, therefore seems strong. However, global policies or recommendations for zinc interventions are few. The World Health Organization recommends zinc only as a curative intervention, either as part of the mineral mix used in the preparation of foods for the treatment of severe malnutrition, or more recently in the treatment of diarrhoea.8 We review current evidence that improving zinc intake has important preventive or curative benefits for mothers and young children and examine the programme implications for achieving this in developing countries.

Sources and selection criteria

We searched PubMed and the databases of WHO and Unicef for information on zinc supplementation and zinc fortification. We examined existing reviews of the evidence for benefits of zinc supplementation and zinc fortification and recent papers reporting the results of randomised controlled trials. These findings were further considered in the light of international policy recommendations for supplementation and fortification of other micronutrients such as iodine, iron, and vitamin …