The findings of the World Health Organization’s Global Burden of Disease project indicated that underweight and micronutrient deficiencies were the main factors underlying child deaths in developing countries. Supplementation with vitamin A, iron, folate, and zinc is widely recommended but there is controversy, particularly about the routine use of iron and folic acid; it is feared that extra iron might favour the growth of bacterial pathogens and malaria parasites. Studies in Zanzibar …