The case of iron: Supplementation vs. Fortification

Iron deficiency is widespread and globally about 1.62 billion people are anemic with the highest prevalence among preschool children (47%) followed by pregnant women (42%). Iron deficiency is the most common cause of anemia and is the most widespread nutritional disorder in the world. A number of public health strategies have been devised to reduce the burden of iron deficiency and anemia. Broadly, these include education to improve iron intake; iron supplementation; iron fortification; bio-fortification; control of malaria and helminthiasis; as well as specific obstetric practices such as active management of the third stage of labor and delayed cord clamping.A recent review shows that daily iron supplementation in pregnancy results in a 69% reduction in incidence of anemia at term, 66% reduction in iron deficiency anemia at term and 20% in incidence of low birth weight.  Iron supplementation also had a significant effect on mean birth weight (mean difference MD: 42.18 [9.27, 75.09]). There was no effect on incidence of preterm birth or that of small for gestation age birth. This review also shows that there is no difference between intermittent iron/iron folic acid supplementation and daily supplementation. A Cochrane review of 33 studies for impact of supplementation on children found that intermittent iron supplementation reduced the risk of anemia by 49% and iron deficiency by 76% and significantly improved hemoglobin (MD: 5.20 g/L, 95% CI 2.51 to 7.88) and ferritin concentrations (MD 14.17 μg/L, 95% CI 3.53 to 24.81). These findings suggest that intermittent iron supplementation may be a viable public health intervention in settings where daily supplementation has failed or has not been implemented. There have been concerns about the safety of iron supplementation in malaria endemic areas and hence the search for alternative strategies for preventing iron deficiency anemia. Relatively few studies have compared supplementation and fortification head to head and in general supplementation dosage is significantly higher than fortification. One study suggested that fortification could be 50% less effective than supplementation, but this was not based on a concurrent comparison. Other studies from a randomized placebo-controlled trial have shown that in anemic schoolchildren, iron fortification was 58% (based on change in hemoglobin level), 80% (based on Serum Ferritin level), and 69% (based on body iron) less effective than iron supplementation but could be beneficial in the long term. Our review confirms the effectiveness of iron fortification strategies. The decision to use one strategy versus another would be based on programmatic opportunities, feasibility and cost effectiveness.