1 UFSJ, UFMG, Belo Horizonte, Brasil. 2 FHEMIG / FAPEMIG, 3 UFBA
Introduction / Objective: Anemia and iron deficiency in childhood has a high prevalence in all regions of Brazil, considered an important public health problem. Food fortification is a viable strategy in developing countries to combat this nutritional deficiency. The addition of iron to potable drinking water is one alternative to the control and prevention of iron deficiency and anemia. This rather simple method can reach a large part of the Brazilian population at each level of the social-economic stratum by the use of drinking water on a daily basis. Drinking water, other than used for drinking, is commonly used for preparation of foods, which may contribute even more towards increasing iron ingestion. In this review, we focus on data of nutritional supplementation interventions with water in order to reduce and prevent this micronutrient deficiency in Brazil. Development: In recent decades, some intervention studies with water fortified with iron were performed in the states of São Paulo (SP) and Minas Gerais (MG). In Ribeirão Preto (SP) a sample of 31 preschool children aged two to six years enrolled in daycare facilities were enrolled in a intervention study. During eight months, children consumed iron-fortified drinking water (20 mg Fe/Liter) which resulted in a significant decrease in the prevalence of anemia. At baseline, anemia prevalence occurred in 58% of subjects. At four months, 16% continued anemic, but at eight months post-study intervention anemia virtually disappeared since anemia was present in only 3% of subjects. Mean hemoglobin at baseline levels (106 ± 11 g/L) increased significantly to 121 ± 14 g/L at four months, and 130 ± 11 g/L at study end. Later, 21 families were followed during four months were divided in experimental and control groups. In the experimental group, family members consumed iron-fortified drinking water containing 10 mg of ferrous sulfate plus 60 mg of ascorbic acid per liter of water. The control group consumed drinking water without the addition of iron or ascorbic acid. Hemoglobin levels in children Increased from 109 ± 11 g/L to 117 ± 11 g/L after four months of fortification intervention. Similar result was find in the experimental group in which adult hemoglobin increased levels (129 ± 17 g/dL to 137 ± 17 g/L). In another study, 160 preschool children from eight municipal daycare facilities benefited from daily consumption of iron (12 g iron element/L) plus ascorbic acid (90 mg/L) prepared in 20-L plastic water jugs. Mean hemoglobin at baseline and after eight months of intervention significantly increased from 118 ± 13 g/L to 124 ± 9.3 g/L, respectively. The prevalence of iron deficiency determined by hemoglobin levels decreased from 43% to 21% at eight months post intervention. In Belo Horizonte (MG), a longitudinal study evaluated the effectiveness of fortification of drinking water with iron and vitamin C in the reduction of the anemia as well as to identify the prevalence of anemia in day care centers. It was evaluated 380 children aged six to 74 months. The total number of children evaluated before and after the fortification was 318, being 52.2% male, with average of 45.4 ± 15.8 months. The prevalence of anemia decreased significantly from 29.3% before the fortification, to 7.9% at the end of the study (p <0.001). According the prevalence by age group, a reduction of 62.5%, 75% and 78.8% were detect in children 24 months age, 24 to 48 months and > 48 months, respectively. The median hemoglobin significant increase in all age groups. The fortification of water with iron and vitamin C significantly reduced the prevalence of anemia in children attending daycare centers. In Diamantina (MG) another study shown also a positive impact of fortified water in a sample of 160 preschoolers. During 8 months, children received drinking water fortified with 12 mg of iron and 60 mg of ascorbic acid per liter of water. There were improvement in hemoglobin levels and anthropometric before and after the intervention. Regarding the toxic effects the literature draws attention to ingestion of large amounts of iron. Important to note the role of iron in the body and the fine balance achieved by controlling their absorption and excretion, as well as the multiplicity of factors and nutrients involved in homeostasis. Longitudinal epidemiological studies to assess the impact of fortification in the incidence of diseases associated with oxidative stress can further clarify the risks. Conclusion: Studies show the positive impact of fortified water in reducing the prevalence of anemia using ferrous sulfate with vitamin C in drinking water for consumption in nurseries and households. The direct costs of food fortification is low if compared to the social costs of iron deficiency and anemia. Key words: food fortification, iron fortification, iron deficiency anemia.