Efficacy of iron-fortified whole maize flour on iron status of schoolchildren in Kenya: a randomised controlled trial

Influence of inflammatory disorders and infection on iron absorption and efficacy of iron-fortified foods

The provision of iron- fortified foods is a common strategy to prevent iron deficiency; however, ensuring adequate iron absorption is a challenge. Iron bioavailability depends on the choice of iron compound, the presence enhancers and inhibitors of absorption in the food matrix, and the physiological state of the consumer, including iron status, other nutritional deficiencies and inflammatory disorders. Inflammation associated with infections and inflammatory disorders would be expected to decrease iron absorption and reduce the efficacy of iron- fortified foods. The decreased absorption is due to an increase in circulating hepcidin in response to inflammatory cytokines. Hepcidin degrades ferroportin and blocks the passage of iron from the intestinal cell to the plasma. This is the innate immune response to infections and aims to restrict pathogen growth by restricting iron supply. Stable isotope studies have reported women and children with chronic malaria parasitemia or febrile malaria to have increased inflammatory cytokines, increased hepcidin and much decreased iron absorption. No studies have specifically investigated the efficacy of iron- fortified foods in the absence and presence of infections. In contrast, inflammation and increased hepcidin associated with adiposity in overweight have been linked to both lower iron absorption and the decreased efficacy of iron- fortified foods.

Relationship of the availability of micronutrient powder with iron status and hemoglobin among women and children in the Kakuma Refugee Camp, Kenya

BACKGROUND

Micronutrient powder is a potential strategy to improve iron status and reduce anemia in refugee populations.

OBJECTIVE

To evaluate the effect of the availability of home fortification with a micronutrient powder containing 2.5 mg of sodium iron ethylenediaminetetraacetate (NaFeEDTA) on iron status and hemoglobin in women and children in the Kakuma Refugee Camp in northwest Kenya.

METHODS

Hemoglobin and soluble transferrin receptor were measured in 410 children 6 to 59 months of age and 458 women of childbearing age at baseline (just before micronutrient powder was distributed, along with the regular food ration) and at midline (6 months) and endline (13 months)follow-up visits.

RESULTS

At the baseline, midline, and endline visits, respectively, the mean (+/- SE) hemoglobin concentration in women was 121.4 +/- 0.8, 120.8 +/- 0.9, and 120.6 +/- 1.0 g/L (p = .42); the prevalence of anemia (hemoglobin < 120 g/L) was 42.6%, 41.3%, and 41.7% (p = .92); and the mean soluble transferrin receptor concentration was 24.1 +/- 0.5, 20.7 +/- 0.7, and 20.8 +/- 0.7 nmol/L (p = .0006). In children, the mean hemoglobin concentration was 105.7 +/- 0.6, 109.0 30322 1.5, and 105.5 +/- 0.3 g/L (p = .95), respectively; the prevalence of anemia (hemoglobin < 110 g/L) was 55.5%, 52.3%, and 59.8% (p = .26); and the mean soluble transferrin receptor concentration was 36.1 +/- 0.7, 29.5 +/- 1.9, and 28.4 +/- 3.2 nmol/L (p = .02), in models that were adjusted for age using least squares means regression.

CONCLUSIONS

In children and in women of childbearing age, the availability of micronutrient powder was associated with a small improvement in iron status but no significant change in hemoglobin in this refugee camp setting.

Fermented soyabean and vitamin C-rich fruit: a possibility to circumvent the further decrease of iron status among iron-deficient pregnant women in Indonesia

Objective

Increasing the consumption of Fe-rich foods and thus improving Fe bioavailability without significantly increasing diet cost is the most sustainable intervention for improving Fe intake. We assessed the effect of supplementary food consisting of fermented soyabean (tempeh) and vitamin C-rich fruit consumed during pregnancy on maternal iron deficiency (ID).

Design

Pregnant women were randomly allocated by village into optimized diet and control groups. Supplementary food was given 6 d/week at home. The average weekly food provided comprised 600 g of tempeh, 30 g of meat, 350 g of guava, 300 g of papaya and 100 g of orange. Hb, ferritin and transferrin receptor (TfR) concentrations were measured at 12–20 and at 32–36 weeks of gestation.

Setting

Thirty-nine villages in Indonesia.

Subjects

Pregnant women (12–20 weeks of gestation, n 252).

Results

At baseline, mean Hb, ferritin and TfR concentrations and body Fe concentration were within the normal range and did not differ between groups. At near term, mean Hb, ferritin and body Fe decreased, whereas mean TfR increased significantly in both groups. The mean changes in Fe status were similar in both groups. In Fe-deficient women, consumption of an optimized diet was associated with smaller decreases in Hb (1·02 (95 % CI 0·98, 1·07) g/l; P = 0·058), ferritin (1·42 (95 % CI 1·16, 1·75) μg/l; P = 0·046) and body Fe (2·57 (95 % CI 1·71, 3·43) mg/kg; P = 0·073) concentrations, compared with a state of no intervention. Fe-deficient women at baseline benefited more from supplementary food compared with Fe-replete women.

Conclusions

Daily supplementary food containing tempeh and vitamin C-rich fruits during pregnancy might have positive effects on maternal ID.

Afebrile Plasmodium falciparum parasitemia decreases absorption of fortification iron but does not affect systemic iron utilization: a double stable-isotope study in young Beninese women

BACKGROUND

Iron deficiency anemia (IDA) affects many young women in sub-Saharan Africa. Its etiology is multifactorial, but the major cause is low dietary iron bioavailability exacerbated by parasitic infections such as malaria.

OBJECTIVE

We investigated whether asymptomatic Plasmodium falciparum parasitemia in Beninese women would impair absorption of dietary iron or utilization of circulating iron.

DESIGN

Iron absorption and utilization from an iron-fortified sorghum-based meal were estimated by using oral and intravenous isotope labels in 23 afebrile women with a positive malaria smear (asexual P. falciparum parasitemia; > 500 parasites/μL blood). The women were studied while infected, treated, and then restudied 10 d after treatment. Iron status, hepcidin, and inflammation indexes were measured before and after treatment.

RESULTS

Treatment reduced low-grade inflammation, as reflected by decreases in serum ferritin, C-reactive protein, interleukin-6, interleukin-8, and interleukin-10 (P < 0.05); this was accompanied by a reduction in median serum hepcidin of ≈ 50%, from 2.7 to 1.4 nmol/L (P < 0.005). Treatment decreased serum erythropoietin and growth differentiation factor 15 (P < 0.05). Clearance of parasitemia increased geometric mean dietary iron absorption (from 10.2% to 17.6%; P = 0.008) but did not affect systemic iron utilization (85.0% compared with 83.1%; NS).

CONCLUSIONS

Dietary iron absorption is reduced by ≈ 40% in asymptomatic P. falciparum parasitemia, likely because of low-grade inflammation and its modulation of circulating hepcidin. Because asymptomatic parasitemia has a protracted course and is very common in malarial areas, this effect may contribute to IDA and blunt the efficacy of iron supplementation and fortification programs. This trial was registered at clinicaltrials.gov as NCT01108939.

The effects of iron fortification on the gut microbiota in African children: a randomized controlled trial in Cote d'Ivoire

BACKGROUND

Iron is essential for the growth and virulence of many pathogenic enterobacteria, whereas beneficial barrier bacteria, such as lactobacilli, do not require iron. Thus, increasing colonic iron could select gut microbiota for humans that are unfavorable to the host.

OBJECTIVE

The objective was to determine the effect of iron fortification on gut microbiota and gut inflammation in African children.

DESIGN

In a 6-mo, randomized, double-blind, controlled trial, 6-14-y-old Ivorian children (n = 139) received iron-fortified biscuits, which contained 20 mg Fe/d, 4 times/wk as electrolytic iron or nonfortifoed biscuits. We measured changes in hemoglobin concentrations, inflammation, iron status, helminths, diarrhea, fecal calprotectin concentrations, and microbiota diversity and composition (n = 60) and the prevalence of selected enteropathogens.

RESULTS

At baseline, there were greater numbers of fecal enterobacteria than of lactobacilli and bifidobacteria (P < 0.02). Iron fortification was ineffective; there were no differences in iron status, anemia, or hookworm prevalence at 6 mo. The fecal microbiota was modified by iron fortification as shown by a significant increase in profile dissimilarity (P < 0.0001) in the iron group as compared with the control group. There was a significant increase in the number of enterobacteria (P < 0.005) and a decrease in lactobacilli (P < 0.0001) in the iron group after 6 mo. In the iron group, there was an increase in the mean fecal calprotectin concentration (P < 0.01), which is a marker of gut inflammation, that correlated with the increase in fecal enterobacteria (P < 0.05).

CONCLUSIONS

Anemic African children carry an unfavorable ratio of fecal enterobacteria to bifidobacteria and lactobacilli, which is increased by iron fortification. Thus, iron fortification in this population produces a potentially more pathogenic gut microbiota profile, and this profile is associated with increased gut inflammation. This trial was registered at controlled-trials.com as ISRCTN21782274.

The nutritional status of school-aged children: why should we care?

BACKGROUND

The nutritional status of school-aged children impacts their health, cognition, and subsequently their educational achievement. The school is an opportune setting to provide health and nutrition services to disadvantaged children. Yet, school-aged children are not commonly included in health and nutrition surveys. An up-to-date overview of their nutritional status across the world is not available.

OBJECTIVE

To provide a summary of the recent data on the nutritional status of school-aged children in developing countries and countries in transition and identify issues of public health concern.

METHODS

A review of literature published from 2002 to 2009 on the nutritional status of children aged 6 to 12 years from Latin America, Africa, Asia, and the Eastern Mediterranean region was performed. Eligible studies determined the prevalence of micronutrient deficiencies or child under- and overnutrition using biochemical markers and internationally accepted growth references.

RESULTS

A total of 369 studies from 76 different countries were included. The available data indicate that the nutritional status of school-aged children in the reviewed regions is considerably inadequate. Underweight and thinness were most prominent in populations from South-East Asia and Africa, whereas in Latin America the prevalence of underweight or thinness was generally below 10%. More than half of the studies on anemia reported moderate (> 20%) or severe (> 40%) prevalence of anemia. Prevalences of 20% to 30% were commonly reported for deficiencies of iron, iodine, zinc, and vitamin A. The prevalence of overweight was highest in Latin American countries (20% to 35%). In Africa, Asia, and the Eastern Mediterranean, the prevalence of overweight was generally below 15%.

CONCLUSIONS

The available data indicate that malnutrition is a public health issue in school-aged children in developing countries and countries in transition. However, the available data, especially data on micronutrient status, are limited. These findings emphasize the need for nutrition interventions in school-aged children and more high-quality research to assess nutritional status in this age group.

Efficacy of pandesal baked from wheat flour fortified with iron and vitamin a in improving the iron and anthropometric status of anemic schoolchildren in the Philippines

OBJECTIVE

To determine the efficacy of pandesal baked from wheat flour fortified with iron, with or without vitamin A (VA), in improving anemic schoolchildren's iron and anthropometric status.

METHODS

Anemic 6- to 12-year-old Filipino children (n = 250) received two 60 g pandesal daily for 8 months. They were randomized into 1 of 4 groups: (1) iron-fortified (with hydrogen-reduced iron at 80 mg/kg, electrolytic iron at 80 mg/kg, or ferrous fumarate at 40 mg/kg), (2) iron and VA-fortified, (3) VA-fortified (at 490 RE/100 g), and (4) nonfortified flour. Hemoglobin (Hb) and zinc protoporphyrin (ZnPP) concentrations and weight and height were determined before and after intervention. Analyses of variance and chi-square and multiple regression analyses were performed.

RESULTS

Mean Hb increased by 1.3 g/dL (p < 0.001) and mean ZnPP decreased by 24.4 micromol/mol (p < 0.001) after 8 months. Anemia decreased to 26% and iron deficiency decreased from 58% to 12%. After controls were applied for baseline concentration, age, and gender, Hb concentration at post intervention was significantly higher in the Iron + VA group than in the nonfortified group (coefficient = 0.37; p = 0.034). The odds of being iron deficient at post intervention were significantly lower in the Iron group than in the nonfortified group after controls were applied for age, gender, and baseline prevalence (coefficient = 0.12; p = 0.006). None of the 3 fortified groups had significantly different weight-for-age z-score, body mass index-for-age z-score, or height-for-age z-score compared with the nonfortified group after controls were applied for baseline z-scores, age, and gender.

CONCLUSIONS

Our study shows that in a non-malaria-endemic area, iron fortification of flour significantly reduced the prevalence of iron deficiency among anemic schoolchildren, and double fortification with iron and VA significantly improved Hb status.

Food nanotechnology: New leverage against iron deficiency

Reducing the particle size of some iron compounds can improve their bioavailability in rats, without increasing their tendency to cause colour and odour changes when added to foods.

Revised Recommendations for Iron Fortification of Wheat Flour and an Evaluation of the Expected Impact of Current National Wheat Flour Fortification Programs

Background

Iron fortification of wheat flour is widely used as a strategy to combat iron deficiency.

Objective

To review recent efficacy studies and update the guidelines for the iron fortification of wheat flour.

Methods

Efficacy studies with a variety of iron-fortified foods were reviewed to determine the minimum daily amounts of additional iron that have been shown to meaningfully improve iron status in children, adolescents, and women of reproductive age. Recommendations were computed by determining the fortification levels needed to provide these additional quantities of iron each day in three different wheat flour consumption patterns. Current wheat flour iron fortification programs in 78 countries were evaluated.

Results

When average daily consumption of low-extraction (≤ 0.8% ash) wheat flour is 150 to 300 g, it is recommended to add 20 ppm iron as NaFeEDTA, or 30 ppm as dried ferrous sulfate or ferrous fumarate. If sensory changes or cost limits the use of these compounds, electrolytic iron at 60 ppm is the second choice. Corresponding fortification levels were calculated for wheat flour intakes of < 150 g/day and > 300 g/day. Electrolytic iron is not recommended for flour intakes of < 150 g/day. Encapsulated ferrous sulfate or fumarate can be added at the same concentrations as the non-encapsulated compounds. For high-extraction wheat flour (> 0.8% ash), NaFeEDTA is the only iron compound recommended. Only nine national programs (Argentina, Chile, Egypt, Iran, Jordan, Lebanon, Syria, Turkmenistan, and Uruguay) were judged likely to have a significant positive impact on iron status if coverage is optimized. Most countries use non-recommended, low-bioavailability, atomized, reduced or hydrogen-reduced iron powders.

Conclusion

Most current iron fortification programs are likely to be ineffective. Legislation needs updating in many countries so that flour is fortified with adequate levels of the recommended iron compounds.

In a randomized controlled trial of iron fortification, anthelmintic treatment, and intermittent preventive treatment of malaria for anemia control in Ivorian children, only anthelmintic treatment shows modest benefit

Anemia is common among children in sub-Saharan Africa and its etiology is multifactorial. Likely causes of anemia are low bioavailability of dietary iron, malaria, and helminth infection. In this study, we aimed to assess the effect of iron fortification, intermittent preventive treatment (IPT) of malaria, and anthelmintic treatment on hemoglobin concentration and anemia prevalence among school children. The study was a 6-mo, randomized, double-blind, controlled trial enrolling 591 6- to 14-y-old school children in Côte d'Ivoire using the following: 1) iron-fortified biscuits providing an additional 20 mg iron/d as electrolytic iron 4 times/wk; 2) IPT of malaria with sulfadoxine-pyrimethamine at 0 and 3 mo; and 3) anthelmintic treatment at 0 and 3 mo as the interventions. Prevalence of anemia, iron deficiency, malaria parasitemia, and helminth infection was 70.4, 9.3, 57.7, and 54.8%, respectively. Iron fortification did not improve iron status, IPT of malaria did not affect malaria burden, and neither had an impact on anemia prevalence. Anthelmintics significantly reduced the burden of helminth infections and decreased anemia prevalence (odds ratio: 0.4, 95% CI: 0.3, 0.7). The low prevalence of iron deficiency and an extended dry season that decreased malaria transmission likely reduced the potential impact of iron fortification and IPT. In this setting, anthelmintic treatment was the only intervention that modestly decreased rates of anemia.

A substantial and confusing variation exists in handling of baseline covariates in randomized controlled trials: a review of trials published in leading medical journals

OBJECTIVE

Statisticians have criticized the use of significance testing to compare the distribution of baseline covariates between treatment groups in randomized controlled trials (RCTs). Furthermore, some have advocated for the use of regression adjustment to estimate the effect of treatment after adjusting for potential imbalances in prognostically important baseline covariates between treatment groups.

STUDY DESIGN AND SETTING

We examined 114 RCTs published in the New England Journal of Medicine, the Journal of the American Medical Association, The Lancet, and the British Medical Journal between January 1, 2007 and June 30, 2007.

RESULTS

Significance testing was used to compare baseline characteristics between treatment arms in 38% of the studies. The practice was very rare in British journals and more common in the U.S. journals. In 29% of the studies, the primary outcome was continuous, whereas in 65% of the studies, the primary outcome was either dichotomous or time-to-event in nature. Adjustment for baseline covariates was reported when estimating the treatment effect in 34% of the studies.

CONCLUSIONS

Our findings suggest the need for greater editorial consistency across journals in the reporting of RCTs. Furthermore, there is a need for greater debate about the relative merits of unadjusted vs. adjusted estimates of treatment effect.

Household Income and Expenditure Surveys: A Tool for Accelerating the Development of Evidence-Based Fortification Programs

Background

One-third of the world's population suffers from micronutrient deficiencies due primarily to inadequate dietary intake. Food fortification is often touted as the most promising short- to medium-term strategy for combating these deficiencies. Despite its appealing characteristics, progress in fortification has been slow.

Objective

To assess the potential of household food-purchase data to fill the food-consumption information gap, which has been an important factor contributing to the slow growth of fortification programs.

Methods

Household income and expenditure survey (HIES) data about: (a) a population's distribution of apparent household consumption, which are essential to setting safe fortification levels, (b) the proportion of households purchasing “fortifiable” food, and (c) the quantity of food being purchased were used to proxy food-consumption data and develop suggested fortification levels.

Results

The usefulness of the approach in addressing several common fortification program design issues is demonstrated. HIES-based suggested fortification levels are juxtaposed with ones developed using the most common current approach, which relies upon Food and Agriculture Organization (FAO) Food Balance Sheets.

Conclusions

Despite its limitations, the use of HIES data constitutes a generally unexploited opportunity to address the food-consumption information gap by using survey data that nearly every country of the world is already routinely collecting. HIES data enable the design of fortification programs to become more based on country-specific data and less on general rules of thumb. The more routine use of HIES data constitutes a first step in improving the precision of fortification feasibility analyses and improving estimates of the coverage, costs, and impact of fortification programs.

Effectiveness of fortification of corn flour-derived products with hydrogen-reduced elemental iron on iron-deficiency anaemia in children and adolescents in southern Brazil

OBJECTIVE

To find the ideal combination of Fe fortifier and its food vehicle is an essential measure in developing countries. However, its cost also plays an important role. In the present study, the effect on blood parameter values of corn flour-derived products fortified with powdered elemental Fe in the form of H2-reduced Fe was investigated in children and adolescents.

METHODS

One hundred and sixty-two individuals (eighty-six boys and seventy-six girls) from public educational centres in Londrina, Paraná (southern Brazil) participated in the study. Fe-deficiency anaemia (IDA) was defined when Hb and serum ferritin values fell below 12 g/dl and 20 microg/l, respectively; Fe deficiency (ID) was considered when serum ferritin was below 20 microg/l.

RESULTS

The prevalence of ID and IDA decreased from 18.0 % and 14.9 %, values found at the beginning of the study, to respectively 5.6 % and 1.2 % after 6 months. Changes from altered to normal values occurred more often than normal to altered values with transferrin saturation (14.2 % v. 6.8 %; P < 0.04) and ferritin (12.4 % v. 0 %; P < 0.001). Hb, transferrin saturation and ferritin showed differences between normal and altered parameters after 6 months (P < 0.001).

CONCLUSION

A pronounced reduction in the prevalence of ID and IDA was observed in children and adolescents following 6 months' ingestion of corn flour-derived products enriched with elemental Fe.

Alpha+ -thalassemia protects against anemia associated with asymptomatic malaria: evidence from community-based surveys in Tanzania and Kenya

BACKGROUND

In hospital-based studies, alpha(+)-thalassemia has been found to protect against severe, life-threatening falciparum malaria. alpha(+)-Thalassemia does not seem to prevent infection or high parasite densities but rather limits progression to severe disease--in particular, severe malarial anemia. We assessed to what extent alpha(+)-thalassemia influences the association between mild, asymptomatic Plasmodium falciparum infection and hemoglobin concentration.

METHODS

The study was based on 2 community-based surveys conducted among afebrile children (0.5-8 years old; n=801) in Kenya and Tanzania.

RESULTS

Among children without inflammation (whole-blood C-reactive protein concentration <or=10 mg/L), P. falciparum infection was associated with only small reductions in hemoglobin concentration, and effects were similar across alpha-globin genotypes. By contrast, the reduction in hemoglobin concentration associated with P. falciparum infection accompanied by inflammation was larger and strongly depended on genotype (normal, -21.8 g/L; heterozygous, -16.7 g/L; and homozygous, -4.6 g/L). Relative to children with a normal genotype, this difference in effect was 5.1 g/L (95% confidence interval [CI], -1.0 to 11.1 g/L) for heterozygotes and 17.2 g/L (95% CI, 8.3 to 26.2 g/L) for homozygotes (estimates are adjusted for study site, age, height-for-age z score, and iron deficiency).

CONCLUSIONS

alpha(+)-Thalassemia limits the decline in hemoglobin concentration that is associated with afebrile infections, particularly those that are accompanied by inflammation.

Fortifying brown bread with sodium iron EDTA, ferrous fumarate, or electrolytic iron does not affect iron status in South African schoolchildren

The choice of iron fortificant usually represents a balance between bioavailability of the compound and its tendency to cause organoleptic problems. The aim of this study was to evaluate the efficacy of sodium iron EDTA (NaFeEDTA) and ferrous fumarate at levels compatible with South African brown bread (10 mg/kg flour for NaFeEDTA and 20 mg/kg flour for ferrous fumarate) in a randomized controlled trial; electrolytic iron was evaluated at the level currently used in South Africa (35 mg/kg flour). Schoolchildren (n = 361), aged 6-11 y, from a low socioeconomic community with hemoglobin (Hb) < or = 125 g/L were randomly assigned to 1 of 4 groups that received 4 slices of brown bread supplying either: 1) no fortification iron 2) 2.35 mg iron as NaFeEDTA; 3) 4.70 mg iron as ferrous fumarate; and 4) 8.30 mg iron as electrolytic iron per intervention day. These amounts simulated a bread intake of 6 slices per day over the 34-wk study period at fortification levels of 0, 10, 20, and 35 mg/kg flour, respectively. Hb concentration and iron status were assessed at baseline and after 34 wk of intervention. The iron interventions did not affect Hb concentration, transferrin saturation, or serum ferritin, iron, or transferrin receptor concentrations relative to the control group. Our results suggest that electrolytic iron at the level currently used in South Africa is not effective in improving iron or Hb status. Neither do NaFeEDTA or ferrous fumarate appear to be suitable alternatives for the fortification of wheat flour when included at levels that do not cause color changes.

What works? Interventions for maternal and child undernutrition and survival

We reviewed interventions that affect maternal and child undernutrition and nutrition-related outcomes. These interventions included promotion of breastfeeding; strategies to promote complementary feeding, with or without provision of food supplements; micronutrient interventions; general supportive strategies to improve family and community nutrition; and reduction of disease burden (promotion of handwashing and strategies to reduce the burden of malaria in pregnancy). We showed that although strategies for breastfeeding promotion have a large effect on survival, their effect on stunting is small. In populations with sufficient food, education about complementary feeding increased height-for-age Z score by 0.25 (95% CI 0.01-0.49), whereas provision of food supplements (with or without education) in populations with insufficient food increased the height-for-age Z score by 0.41 (0.05-0.76). Management of severe acute malnutrition according to WHO guidelines reduced the case-fatality rate by 55% (risk ratio 0.45, 0.32-0.62), and recent studies suggest that newer commodities, such as ready-to-use therapeutic foods, can be used to manage severe acute malnutrition in community settings. Effective micronutrient interventions for pregnant women included supplementation with iron folate (which increased haemoglobin at term by 12 g/L, 2.93-21.07) and micronutrients (which reduced the risk of low birthweight at term by 16% (relative risk 0.84, 0.74-0.95). Recommended micronutrient interventions for children included strategies for supplementation of vitamin A (in the neonatal period and late infancy), preventive zinc supplements, iron supplements for children in areas where malaria is not endemic, and universal promotion of iodised salt. We used a cohort model to assess the potential effect of these interventions on mothers and children in the 36 countries that have 90% of children with stunted linear growth. The model showed that existing interventions that were designed to improve nutrition and prevent related disease could reduce stunting at 36 months by 36%; mortality between birth and 36 months by about 25%; and disability-adjusted life-years associated with stunting, severe wasting, intrauterine growth restriction, and micronutrient deficiencies by about 25%. To eliminate stunting in the longer term, these interventions should be supplemented by improvements in the underlying determinants of undernutrition, such as poverty, poor education, disease burden, and lack of women's empowerment.

Maize meal fortification is associated with improved vitamin A and iron status in adolescents and reduced childhood anaemia in a food aid-dependent refugee population

OBJECTIVE

To assess changes in the Fe and vitamin A status of the population of Nangweshi refugee camp associated with the introduction of maize meal fortification.

DESIGN

Pre- and post-intervention study using a longitudinal cohort.

SETTING

Nangweshi refugee camp, Zambia.

SUBJECTS

Two hundred and twelve adolescents (10-19 years), 157 children (6-59 months) and 118 women (20-49 years) were selected at random by household survey in July 2003 and followed up after 12 months.

RESULTS

Maize grain was milled and fortified in two custom-designed mills installed at a central location in the camp and a daily ration of 400 g per person was distributed twice monthly to households as part of the routine food aid ration. During the intervention period mean Hb increased in children (0.87 g/dl; P < 0.001) and adolescents (0.24 g/dl; P = 0.043) but did not increase in women. Anaemia decreased in children by 23.4% (P < 0.001) but there was no significant change in adolescents or women. Serum transferrin receptor (log10-transformed) decreased by -0.082 microg/ml (P = 0.036) indicating an improvement in the Fe status of adolescents but there was no significant decrease in the prevalence of deficiency (-8.5%; P = 0.079). In adolescents, serum retinol increased by 0.16 micromol/l (P < 0.001) and vitamin A deficiency decreased by 26.1% (P < 0.001).

CONCLUSIONS

The introduction of fortified maize meal led to a decrease in anaemia in children and a decrease in vitamin A deficiency in adolescents. Centralised, camp-level milling and fortification of maize meal is a feasible and pertinent intervention in food aid operations.

Tissue iron distribution and urinary mineral excretion vary depending on the form of iron (FeSO4 or NaFeEDTA) and the route of administration (oral or subcutaneous) in rats given high doses of iron

Sodium iron ethylenediaminetetraacetate (NaFeEDTA) has considerable promise as an iron fortificant in food. However, effects of administering high levels of NaFeEDTA on tissue iron distribution and mineral excretion are not well understood. The objectives of this study were to assess nonheme iron distribution in the body and urinary excretion of Ca, Mg, Cu, Fe, and Zn after daily administration of high levels of iron to rats over 21 days. Iron was either given orally with food or injected subcutaneously, as either FeSO 4 or NaFeEDTA. Selected tissues were collected for nonheme iron analysis. Estimated total body nonheme iron levels were similar in rats fed NaFeEDTA or FeSO 4, but the tissue distribution was different: it was 53% lower in the liver and 86% higher in the kidneys among rats fed NaFeEDTA than among those fed FeSO 4. In contrast, body nonheme iron was 3.2-fold higher in rats injected with FeSO 4 than in rats injected with NaFeEDTA. Administering NaFeEDTA orally elevated urinary Cu, Fe, and Zn excretion compared with FeSO 4 (1.41-, 11.9-, and 13.9-fold higher, respectively). We conclude that iron is dissociated from the EDTA complex prior to or during intestinal absorption. A portion of intact FeEDTA may be absorbed via a paracellular route at high levels of intake but is mostly excreted in the urine. Metal-free EDTA may be absorbed and cause elevated urinary excretion of Fe, Cu, and Zn.

Nutritional iron deficiency

Iron deficiency is one of the leading risk factors for disability and death worldwide, affecting an estimated 2 billion people. Nutritional iron deficiency arises when physiological requirements cannot be met by iron absorption from diet. Dietary iron bioavailability is low in populations consuming monotonous plant-based diets. The high prevalence of iron deficiency in the developing world has substantial health and economic costs, including poor pregnancy outcome, impaired school performance, and decreased productivity. Recent studies have reported how the body regulates iron absorption and metabolism in response to changing iron status by upregulation or downregulation of key intestinal and hepatic proteins. Targeted iron supplementation, iron fortification of foods, or both, can control iron deficiency in populations. Although technical challenges limit the amount of bioavailable iron compounds that can be used in food fortification, studies show that iron fortification can be an effective strategy against nutritional iron deficiency. Specific laboratory measures of iron status should be used to assess the need for fortification and to monitor these interventions. Selective plant breeding and genetic engineering are promising new approaches to improve dietary iron nutritional quality.