LINEAMIENTOS ALTERNATIVOS
PLANTEAMIENTO DEL PROBLEMA
The first section pointed out some of the practical and conceptual issues involved in estimating the economic magnitude of costs both of iron defi- ciency and of interventions designed to reduce nutritional anemia. None of these issues are insu- perable, and Section 2 provided some estimates of the costs of iron deficiency, through three of the key mechanisms. Current studies (looking at broader impact, for example self-employment earnings, and longitudinal studies of children who received iron interventions) serve to endorse still further the heavy costs of iron deficiency.
Policy-makers are not unaware of the costs of deficiency, but the key issue for policy has been the difficulties in finding cost-effective interven- tions which reduce iron deficiency, previously measured using anemia rates, and now preferably by blood hemoglobin level.
Given the very high proportion of the popula- tion with iron deficiency or anemia in most devel- oping countries, mandatory fortification of some widely consumed foods should be considered in all countries. Although there is some leakage to non-deficient populations, these costs, in many situations, are likely less than that incurred by tar- geting and may not have a substantial effect on cost-effectiveness. The literature considers possi- ble risks (in malarial areas, and to individuals with conditions such as thalassemia), but in gen- eral the good of the overall population is consid- ered of overriding importance. Estimated costs are of the order of $0.10–$1.00 per person per year, with the benefit-to-cost ratio to the order of 6:1 (physical benefits to adults) or as high as 9:1 (also including estimated cognitive benefits to children).
Supplementation has an important role for selected population groups, particularly pregnant and lactating women, whose needs cannot be met by fortification; however continued operational research is required to design programs which work cost-effectively in the field. Home fortifica- tion (a kind of hybrid between fortification and supplementation) holds considerable promise for groups who cannot readily be reached by fortifi- cation, such as weaning-age children, and vulner- able groups in areas not reached by commer- cially-processed foods or who purchase only small quantities of such foods. Supplementation costs are of the order of $2.00-5.00 per person per year, and in favorable circumstances economic benefits may exceed costs. Home fortification tar- geted at small children at vulnerable ages might have a similar cost, but a better benefit-to-cost ratio.
The importance of deworming has probably been overlooked. Several recent studies of both
3The study only presents estimates for a discount rate of 3%. Under the assumption that the benefits are distributed evenly over the
fortification and supplementation suggest that it works synergistically with fortification and sup- plementation, rendering both likely to be more cost-effective. While it has been primarily used for school-age children, it may be as important if not even more important for preschool children. One hypothesis is that although worm loads are lower in younger children, the impact on absorb- tion in the gut is more disruptive (38). There are studies suggesting programs can cost-effectively reach preschool children (44). Costs are approxi- mately $0.50/person/year, and the benefit-to-cost ratio may be comparable to that for fortification.
The interventions discussed above should not divert emphasis from long run solutions such as increased dietary diversity, agricultural improve- ments, and rising income. Biofortification is one possible way to enhance such long run efforts. This has potentially low costs per person (although the fixed costs are high, the benefits can reach millions of people), and potentially favor- able benefit-to-cost ratios, although this remains to be proven.
33 The economics of adressing nutritional anemia
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35 The economics of adressing nutritional anemia