Prevention of iron-deficiency anemia: comparison of high- and low-iron formulas in term healthy infants after six months of life

A Systematic Review of Isotopically Measured Iron Absorption in Infants and Children Under 2 Years

BACKGROUND

Iron is an essential element for critical biological functions, with iron deficiency negatively affecting growth and brain development and iron excess associated with adverse effects. The goal of this review is to provide a comprehensive assessment of up-to-date evidence on iron absorption measured isotopically in children, preterm infants, and full-term infants, up to 24 months of age.

METHODS

Search databases included Pubmed, Cochrane, Web of Science, and Scopus from a date range of 1 January 1953 to 22 July 2024. The included articles were experimental studies with iron absorption outcomes measured by isotopic techniques. The risk of bias was assessed using the Cochrane Risk of Bias Tool.

RESULTS

A total of 1594 records were identified from databases, and 37 studies were included in the quality review with a total of 1531 participants. Article results were grouped by study commonality: absorption and red blood cell incorporation, type of milk feedings, additives to improve absorption, how and when to supplement with iron, and iron forms and complimentary foods.

CONCLUSIONS

The results from this review support the current recommendations of oral iron supplementation. Iron from breast milk has high bioavailability, and unmodified cow's milk reduces iron absorption. Supplemental iron is required at 4-6 months for healthy, full-term infants and sooner for preterm infants. Ascorbic acid increases iron absorption in full-term infants and children. Lactoferrin and prebiotics are promising candidates for enhancing iron absorption, but they require further investigation. Research evidence of iron absorption mechanisms and modulating factors in preterm infants is limited and should be a research priority.

Universal iron supplementation: the best strategy to tackle childhood anaemia in malaria-endemic countries?

Iron deficiency presents a major public health concern in many malaria-endemic regions, and both conditions affect young children most severely. Daily iron supplementation is the standard public health intervention recommended to alleviate rates of iron deficiency in children, but there is controversy over whether universal supplementation could increase the incidence and severity of malaria infection. Current evidence suggests that iron supplementation of deficient individuals is safe and effective in high-transmission settings when accompanied by malaria prevention strategies. However, low-resource settings often struggle to effectively control the spread of malaria, and it remains unclear whether supplementation of iron replete individuals could increase their risk of malaria and other infections. This review explores the evidence for and against universal iron supplementation programmes, and alternative strategies that could be used to alleviate iron deficiency in malaria-endemic areas, while minimising potential harm.

Breastfeeding Duration and Timing of Bottle Supplementation: Associations with Body Mass Index from Childhood to Young-Adulthood

Evidence for the association between breastfeeding (BF) duration and later body mass index (BMI) is inconsistent. We explored how BF duration and BF type (exclusive or partial) related to BMI from childhood to young adulthood in a Chilean cohort. Infants were recruited at 6 months between 1994 and 1996 in Santiago, Chile (n = 821). Mothers reported date of first bottle and last BF; anthropometry was measured at 1, 5, 10, 16, and 23 years. We tested whether: (1) type of BF at 6 months (none, partial, exclusive) and (2) duration of exclusive BF (<1 month, 1 to <3 months, 3 to <6 months, and ≥6 months) related to BMI. At 6 months, 35% received both breastmilk and formula ("partial BF") and 38% were exclusively breastfed. We found some evidence of an association between longer BF and lower BMI z-scores at young ages but observed null effects for later BMI. Specifically, BF for 3 to <6 months compared to <1 month related to lower BMI z-scores at 1 and 5 years (both p < 0.05). Our results are in partial accordance with others who have not found a protective effect of longer BF for lower BMI.

Prenatal iodine supplementation and early childhood neurodevelopment: the PoppiE trial - study protocol for a multicentre randomised controlled trial

INTRODUCTION

Observational studies suggest both low and high iodine intakes in pregnancy are associated with poorer neurodevelopmental outcomes in children. This raises concern that current universal iodine supplement recommendations for pregnant women in populations considered to be iodine sufficient may negatively impact child neurodevelopment. We aim to determine the effect of reducing iodine intake from supplements for women who have adequate iodine intake from food on the cognitive development of children at 24 months of age.

METHODS AND ANALYSIS

A multicentre, randomised, controlled, clinician, researcher and participant blinded trial with two parallel groups. Using a hybrid decentralised clinical trial model, 754 women (377 per group) less than 13 weeks' gestation with an iodine intake of ≥165 µg/day from food will be randomised to receive either a low iodine (20 µg/day) multivitamin and mineral supplement or an identical supplement containing 200) µg/day (amount commonly used in prenatal supplements in Australia), from enrolment until delivery. The primary outcome is the developmental quotient of infants at 24 months of age assessed with the Cognitive Scale of the Bayley Scales of Infant Development, fourth edition. Secondary outcomes include infant language and motor development; behavioural and emotional development; maternal and infant clinical outcomes and health service utilisation of children. Cognitive scores will be compared between groups using linear regression, with adjustment for location of enrolment and the treatment effect described as a mean difference with 95% CI.

ETHICS AND DISSEMINATION

Ethical approval has been granted from the Women's and Children's Health Network Research Ethics Committee (HREC/17/WCHN/187). The results of this trial will be presented at scientific conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04586348.

Iron and DHA in Infant Formula Purchased in the US Fails to Meet European Nutrition Requirements

Requirements for iron and docosahexaenoic acid (DHA) content of infant formula varies by country. Powdered full-term infant formula purchase data from all major physical stores in the US between 2017-2019 were obtained from CIRCANA, Inc. Iron and DHA composition and scoop sizes for each formula were obtained from manufacturers. The equivalent liquid ounces of prepared formula were calculated. Average iron and DHA content were compared between formula types and to both US and European formula composition requirements. These data represent 55.8 billion ounces of formula. The average iron content of all formula purchased was: 1.80 mg/100 kcal. This iron concentration is within the FDA regulations. However, it exceeds the maximum allowable iron concentration of infant formula (Stage 1) set by the European Commission of 1.3 mg/100 kcal. A total of 96% of formula purchased had an iron concentration of >1.3 mg/100 kcal. DHA is not a required ingredient in US formulas. The average DHA content of all formula purchased was: 12.6 mg/100 kcal. This DHA concentration is far below the minimum required DHA concentrations of infant formula (Stage 1) and follow-on formula (Stage 2) set by the European Commission of 20 mg/100 kcal. These are novel insights into the iron and DHA intake of formula-fed infants in the US. As international infant formulas have entered the US market due to the formula shortage, parents and providers need to be aware of regulatory differences in formula nutrient composition.

Benefits and Risks of Early Life Iron Supplementation

Infants are frequently supplemented with iron to prevent iron deficiency, but iron supplements may have adverse effects on infant health. Although iron supplements can be highly effective at improving iron status and preventing iron deficiency anemia, iron may adversely affect growth and development, and may increase risk for certain infections. Several reviews exist in this area; however, none has fully summarized all reported outcomes of iron supplementation during infancy. In this review, we summarize the risks and benefits of iron supplementation as they have been reported in controlled studies and in relevant animal models. Additionally, we discuss the mechanisms that may underly beneficial and adverse effects.

Determination of trace element and fatty acid levels in tissues of mirror and scaly carp (Cyprinus carpio L., 1758) living in Keban Dam Reservoir (Elazig)

This study investigated the concentrations of some accumulated trace metals (iron, manganese, zinc and copper) and fatty acids in liver and muscle tissues of mirror and scaly carp varieties (Cyprinus carpio L., 1758) living in Keban Dam Reservoir (Elazig), which is the second-largest artificial lake in Turkey that hosts commercially valuable and preferred fish varieties for human consumption. The inductively coupled plasma mass spectrometry (ICP-MS) method was used to analyse the concentrations of trace elements. Fatty acid levels were measured in a gas chromatography mass spectrometry (GC-MS) device, using a flame ionization detector (FID). Considering the two fish varieties and tissues that were studied, the mean metal concentrations (μg g^-1 ) were found in the following ranges: Fe 12.32-49.97, Mn 0.12-0.62, Zn 10.45-86.59 and Cu 2.74-11.86. Although the lowest levels were detected in the muscle tissue for all the metals examined, the levels in the liver tissue were significantly higher. According to the results of the analyses on fatty acid concentrations, the mean total saturated fatty acid levels in the muscle tissue of the scaly carp and mirror carp varieties were found to be 31.07 and 31.43 (%), respectively, whereas these values for the liver tissue were consecutively 22.36 and 22.08 (%). Successively, the mean total levels of unsaturated fatty acids were determined as 68.93 and 68.40 (%) in the muscle tissue and 77.64 and 77.92 in the liver tissue. This study, with the finding that the trace (metallic) element accumulation rates were below the upper limits of the tolerable range, and the examined fish varieties were rich in fatty acids, shows that mirror carp and scaly carp living in Keban Dam Reservoir are highly nutritious for human diets.

Complementary Feeding and Iron Status: "The Unbearable Lightness of Being" Infants

The complementary feeding (CF) period that takes place between 6 and 24 months of age is of key importance for nutritional and developmental reasons during the transition from exclusively feeding on milk to family meals. In 2021, a multidisciplinary panel of experts from four Italian scientific pediatric societies elaborated a consensus document on CF, focusing in particular on healthy term infants. The aim was to provide healthcare providers with useful guidelines for clinical practice. Complementary feeding is also the time window when iron deficiency (ID) and iron deficiency anemia (IDA) are most prevalent. Thus, it is appropriate to address the problem of iron deficiency through nutritional interventions. Adequate iron intake during the first two years is critical since rapid growth in that period increases iron requirements per kilogram more than at any other developmental stage. Complementary foods should be introduced at around six months of age, taking into account infant iron status.

Fetal liver hepcidin secures iron stores in utero

In the adult, the liver-derived hormone hepcidin (HAMP) controls systemic iron levels by blocking the iron-exporting protein ferroportin (FPN) in the gut and spleen, the sites of iron absorption and recycling, respectively. Impaired HAMP expression or FPN responsiveness to HAMP result in iron overload. HAMP is also expressed in the fetal liver but its role in controlling fetal iron stores is not understood. To address this question in a manner that safeguards against the confounding effects of altered maternal iron homeostasis, we generated fetuses harboring a paternally-inherited ubiquitous knock-in of the HAMP-resistant fpnC326Y. Additionally, to safeguard against any confounding effects of altered placental iron homeostasis, we generated fetuses with a liver-specific knock-in of fpnC326Y or knockout of the hamp gene. These fetuses had reduced liver iron stores and hemoglobin, and markedly increased FPN in the liver, but not in the placenta. Thus, fetal liver HAMP operates cell-autonomously to increase fetal liver iron stores. Our findings also suggest that FPN in the placenta is not actively regulated by fetal liver HAMP under normal physiological conditions.

Reducing Iron Content in Infant Formula from 8 to 2 mg/L Does Not Increase the Risk of Iron Deficiency at 4 or 6 Months of Age: A Randomized Controlled Trial

Many infant formulas are fortified with iron at 8-14 mg/L whereas breast milk contains about 0.3 mg/L. Another major difference between breast milk and infant formula is its high concentration of lactoferrin, a bioactive iron-binding protein. The aim of the present study was to investigate how reducing the iron content and adding bovine lactoferrin to infant formula affects iron status, health and development. Swedish healthy full-term formula-fed infants (n = 180) were randomized in a double-blind controlled trial. From 6 weeks to 6 months of age, 72 infants received low-iron formula (2 mg/L) fortified with bovine lactoferrin (1.0 g/L) (Lf+), 72 received low-iron formula un-fortified with lactoferrin (Lf-) and 36 received standard formula with 8 mg of iron/L and no lactoferrin fortification as controls (CF). Iron status and prevalence of iron deficiency (ID) were assessed at 4 and 6 months. All iron status indicators were unaffected by lactoferrin. At 4 and 6 months, the geometric means of ferritin for the combined low-iron groups compared to the CF-group were 67.7 vs. 88.7 and 39.5 vs. 50.9 µg/L, respectively (p = 0.054 and p = 0.056). No significant differences were found for other iron status indicators. In the low-iron group only one infant (0.7%) at 4 months and none at 6 months developed ID. Conclusion: Iron fortification of 2 mg/L is an adequate level during the first half of infancy for healthy term infants in a well-nourished population. Adding lactoferrin does not affect iron status.

Is untargeted iron supplementation harmful when iron deficiency is not the major cause of anaemia? Study protocol for a double-blind, randomised controlled trial among non-pregnant Cambodian women

INTRODUCTION

The WHO recommends daily oral iron supplementation for 12 weeks in women and adolescents where anaemia prevalence is greater than 40%. However, if iron deficiency is not a major cause of anaemia, then, at best, untargeted iron supplementation is a waste of resources; at worst, it could cause harm. Further, different forms of iron with varying bioavailability may present greater risks of harm.

METHODS AND ANALYSIS

A 12-week three-arm, double-blind, randomised controlled supplementation trial was conducted in Cambodia to determine if there is potential harm associated with untargeted iron supplementation. We will recruit and randomise 480 non-pregnant women (ages 18-45 years) to receive one of three interventions: 60 mg elemental iron as ferrous sulfate (the standard, commonly used form), 18 mg ferrous bisglycinate (a highly bioavailable iron amino acid chelate) or placebo. We will measure ferritin concentrations (to evaluate non-inferiority between the two forms of iron), as well as markers of potential harm in blood and stool (faecal calprotectin, gut pathogen abundance and DNA damage) at baseline and 12 weeks. Mixed-effects generalised linear models will be used to assess the effect of iron on ferritin concentration and markers of potential harm at 12 weeks.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the University of British Columbia Clinical Research Ethics Board (H18-02610), the Children's and Women's Health Centre of British Columbia Research Ethics Board (H18-02610) and the National Ethics Committee for Health Research in Cambodia (273-NECHR). Findings will be published in peer-reviewed journals, presented to stakeholders and policymakers globally and shared within participants' communities.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT04017598).

Young children formula consumption and iron deficiency at 24 months in the general population: A national-level study

BACKGROUND & AIMS

Iron deficiency (ID) is considered the most frequent micronutrient deficiency in industrialized countries where strategies for its primary prevention vary widely and are insufficiently evaluated. We aimed to study the effectiveness for iron status of a national iron deficiency prevention strategy based on recommendations for young-child formula (YCF) use after age 12 months, taking into consideration other sources of iron and the family's socio-economic status.

METHODS

In a cross-sectional observational study conducted in primary care pediatrician offices throughout France from 2016 to 2017, infants aged 24 months were consecutively included for a food survey and blood sampling. Associations between YCF consumption and serum ferritin (SF) level were studied by multivariable regression after adjustment on sociodemographic, perinatal and dietary characteristics, notably other intakes of iron.

RESULTS

Among the 561 infants analyzed, the ID prevalence was 6.6% (37/561; 95% confidence interval [CI] 4.7-9.0). Daily iron intake excluding YCF and total daily iron intake including YCF were below the 5-mg/day recommended average requirements for 63% and 18% of children, respectively. ID frequency was significantly decreased (or SF level was independently higher) with any YCF consumption after age 10 months (odds ratio 0.15, 95% CI 0.07-0.31), current YCF consumption at age 24 months (median SF level 29 vs 21 μg/L if none), prolonged YCF consumption (28 μg/L if >12 months vs 17 μg/L if none), and increasing daily volume of YCF consumed at age 24 months from a small volume (e.g., 29 μg/L if <100 mL/day vs 21 μg/L if none).

CONCLUSIONS

Current or past YCF use was independently associated with a better iron status at age 24 months than non-use. The strategy recommending YCF use at weaning after age 12 months seems effective in the general population. CLINICALTRIALS.

GOV IDENTIFIER

NCT02484274.

Standard and Specialized Infant Formulas in Europe: Making, Marketing, and Health Outcomes

Infant formulas are the only suitable substitute for human milk. The most common infant formulas are standard formulas based on cow's milk. In addition, there are formulas for infants showing signs and symptoms of intolerance and for clinical conditions such as allergy, prematurity, and gastrointestinal diseases. A comprehensive review of the literature was made to review the composition of standard and specialized infant formulas and analyze indications for use, real or presumed nutrition differences and properties, and impact on infant growth. A brief consideration on costs is outlined for each formula. Over the past few years, industrial production and advertising of infant formulas have increased. Human milk still remains the most complete source of nutrition for infants and should be continued according to the current recommendations. Few differences exist between infant formulas, both for the nutrition action and the macronutrient/micronutrient composition. Specialized infant formulas have limited indications for use and high costs. The role of the pediatrician is crucial in the management of infant nutrition, promotion of breastfeeding, and prescribing of specialized formulas only in specific clinical conditions.

Randomized Controlled Trial of Iron-Fortified versus Low-Iron Infant Formula: Developmental Outcomes at 16 Years

OBJECTIVES

To test differences in cognitive outcomes among adolescents randomly assigned previously as infants to iron-fortified formula or low-iron formula as part of an iron deficiency anemia prevention trial.

STUDY DESIGN

Infants were recruited from community clinics in low- to middle-income neighborhoods in Santiago, Chile. Entrance criteria included term, singleton infants; birth weight of ≥3.0 kg; and no major congenital anomalies, perinatal complications, phototherapy, hospitalization >5 days, chronic illness, or iron deficiency anemia at 6 months. Six-month-old infants were randomized to iron-fortified (12 mg/L) or low-iron (2.3 mg/L) formula for 6 months. At 16 years of age, cognitive ability, visual perceptual ability, visual memory, and achievement in math, vocabulary, and comprehension were assessed, using standardized measures. We compared differences in developmental test scores according to randomization group.

RESULTS

At the follow-up assessment, the 405 participants averaged 16.2 years of age and 46% were male. Those randomized to iron-fortified formula had lower scores than those randomized to low-iron formula for visual memory, arithmetic achievement, and reading comprehension achievement. For visual motor integration, there was an interaction with baseline infancy hemoglobin, such that the iron-fortified group outperformed the low-iron group when 6-month hemoglobin was low and underperformed when 6-month hemoglobin was high.

CONCLUSIONS

Adolescents who received iron-fortified formula as infants from 6 to 12 months of age at levels recommended in the US had poorer cognitive outcomes compared with those who received a low-iron formula. The prevention of iron deficiency anemia in infancy is important for brain development. However, the optimal level of iron supplementation in infancy is unclear.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT01166451.

Adolescent Internalizing, Externalizing, and Social Problems Following Iron Deficiency at 12-18 Months: The Role of Maternal Responsiveness

This study tested whether maternal responsiveness moderated or mediated pathways from iron deficiency (ID) at 12-18 months to adolescent behavior problems. Participants were part of a large Chilean cohort (N = 933). Iron status was assessed at 12 and 18 months. Maternal responsiveness was assessed at 9 months and 5 years. Parents reported their child's symptomology at 5 years, 10 years, and adolescence (11-17 years; M = 14.4). Structural equation modeling identified a previously unrecognized pathway by which child externalizing problems and negative maternal responsiveness at 5 years mediated associations between ID at 12-18 months and adolescent internalizing, externalizing, and social problems. Positive maternal responsiveness in infancy did not buffer those with ID anemia from developing 5-year internalizing problems.

The Benefits and Risks of Iron Supplementation in Pregnancy and Childhood

Iron deficiency is the most common micronutrient deficiency in the world and disproportionately affects pregnant women and young children. Iron deficiency has negative effects on pregnancy outcomes in women and on immune function and neurodevelopment in children. Iron supplementation programs have been successful in reducing this health burden. However, iron supplementation of iron-sufficient individuals is likely not necessary and may carry health risks for iron-sufficient and potentially some iron-deficient populations. This review considers the physiology of iron as a nutrient and how this physiology informs decision-making about weighing the benefits and risks of iron supplementation in iron-deficient, iron-sufficient, and iron-overloaded pregnant women and children.

Association Between Maternal Iodine Intake in Pregnancy and Childhood Neurodevelopment at Age 18 Months

There are limited and inconsistent data suggesting that mild iodine deficiency in pregnancy might be associated with poorer developmental outcomes in children. Between 2011 and 2015, we conducted a prospective cohort study in Australia examining the relationship between maternal iodine intake in pregnancy and childhood neurodevelopment, assessed using Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III), in 699 children at 18 months. Maternal iodine intake and urinary iodine concentration (UIC) were assessed at study entry (<20 weeks' gestation) and at 28 weeks' gestation. Maternal iodine intake in the lowest (<220 μg/day) or highest (≥391 μg/day) quartile was associated with lower cognitive, language, and motor scores (mean differences ranged from 2.4 (95% confidence interval (CI): 0.01, 4.8) to 7.0 (95% CI: 2.8, 11.1) points lower) and higher odds (odds ratios ranged from 2.7 (95% CI: 1.3, 5.6) to 2.8 (95% CI: 1.3, 5.7)) of cognitive developmental delay (Bayley-III score <1 SD) compared with mothers with an iodine intake in the middle quartiles. There was no association between UIC in pregnancy and Bayley-III outcomes regardless of whether UIC and the outcomes were analyzed as continuous or categorical variables. Both low and high iodine intakes in pregnancy were associated with poorer childhood neurodevelopment in this iodine-sufficient population.

Effects of non-digestive polymers used in iron encapsulation on calcium and iron apparent absorption in rats fed by infant formula

Iron deficiency anemia is a common problem of all ages in developed and developing countries. Various strategies are used by governments and industries to solve this problem. One of these strategies is iron fortification. In the present study, novel iron microcapsules were designed without any changes in their effects on other ingredients in infant milk formulas. Resistant starch-pectin-iron and pectin-iron microparticles were added to infant powdered milk models. Furthermore, animal studies were carried out. Fecal iron and calcium were assessed using flame atomic absorption spectroscopy and inductively coupled plasma optical emission spectroscopy, respectively. Then, apparent iron and calcium absorptions were calculated. Sensory evaluation was carried out on reconstituted powdered milks. Results showed that iron absorption in rats treated by pectin-coated particles was significantly higher than that in controls with no significant effects on calcium absorption. No significant differences were observed in sensory evaluation.

Greater early weight gain and shorter breastfeeding are associated with low adolescent adiponectin levels

BACKGROUND

Early life factors can programme future risk for cardiovascular disease.

OBJECTIVES

We explored associations between adolescent adiponectin levels and concomitant metabolic alteration and also looked at the association between early life factors and adolescent adiponectin levels.

METHODS

We studied a longitudinal cohort of low-income to middle-income Chilean adolescents who were enroled in an infancy iron-deficiency anaemia preventive trial and follow-up studies at the Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile. In the 577 adolescents who were assessed as part of the 16-year follow-up, we evaluated independent associations between adiponectin levels and metabolic disturbances during adolescence. We also assessed the association between early life factors [short breastfeeding {<6 months} and infancy weight gain] and adolescent adiponectin levels.

RESULTS

Participants were 16.8 years old (16.4-18.1), 48% female and 38% overweight/obese. Adolescent adiponectin levels were inversely associated with metabolic disturbances: altered homeostatic model assessment of insulin resistance and high-density lipoprotein cholesterol [odds ratios {95% confidence interval} = 0.87 {0.79-0.95}, p-value = 0.002, and 0.90 {0.87-0.94}, p-value < 0.001, respectively], adjusting for sex and fat mass index. Early life factors were independently associated with adolescent adiponectin levels, which decreased 0.88 ug mL^-1 per each unit increase in weight-for-age z-score between 0 and 6 months and was 1.58 ug mL^-1 lower among participants with short breastfeeding.

CONCLUSIONS

Higher adolescent adiponectin levels were independently associated with lower odds of metabolic disturbances. Greater weight gain during infancy and shorter breastfeeding were associated with lower adolescent adiponectin levels, supporting research indicating early life as a window of opportunity for prevention of later cardiovascular alterations. © 2017 World Obesity Federation.

Excess iron intake as a factor in growth, infections, and development of infants and young children

The provision of iron via supplementation or the fortification of foods has been shown to be effective in preventing and treating iron deficiency and iron deficiency anemia in infants and young children. However, iron is a pro-oxidative element and can have negative effects on biological systems even at moderate amounts. An increasing number of studies have reported adverse effects of iron that was given to infants and young-children populations who initially were iron replete. These effects include decreased growth (both linear growth and weight), increased illness (usually diarrhea), interactions with other trace elements such as copper and zinc, altered gut microbiota to more pathogenic bacteria, increased inflammatory markers, and impaired cognitive and motor development. If these results can be confirmed by larger and well-controlled studies, it may have considerable programmatic implications (e.g., the necessity to screen for iron status before interventions to exclude iron-replete individuals). A lack of understanding of the mechanisms underlying these adverse outcomes limits our ability to modify present supplementation and fortification strategies. This review summarizes studies on the adverse effects of iron on various outcomes; suggests possible mechanisms that may explain these observations, which are usually made in clinical studies and intervention trials; and gives examples from animal models and in vitro studies. With a better understanding of these mechanisms, it may be possible to find novel ways of providing iron in a form that causes fewer or no adverse effects even when subjects are iron replete. However, it is apparent that our understanding is limited, and research in this area is urgently needed.

Breastfeeding as the sole source of milk for 6 months and adolescent bone mineral density

Little is known regarding the relationship between early life factors and bone mineral density (BMD). We found a positive association between breastfeeding for at least 6 months, without formula supplementation, and whole body adolescent BMD z-score.

INTRODUCTION

The aim of the study is to assess the role of breastfeeding BF on adolescent bone mineral density (BMD) in a cohort prospectively followed since infancy.

METHODS

We studied 679 participants from an infancy iron deficiency anemia preventive trial in Santiago, Chile, followed to adolescence. Breast and bottle feeding were ascertained weekly from 4 to 12 months. At 16 years, whole body BMD was assessed by DEXA. Using linear regression, we evaluated associations between BF duration and BF as the sole source of milk and adolescent BMD z-score, adjusting for possible infancy, adolescent, and background confounders.

RESULTS

Mean birth weight and length were 3.5 (0.3) kg and 50.7 (1.6) cm. For at least 6 months, BF was the sole source of milk for 26.3% and with supplementation for 36.7%. For 37%, BF was provided for less than 6 months. Mean 16-year BMD z-score was 0.25 (1.0). Covariates included male sex, birth length, and gestational age. BF as the sole source of milk ≥6 months, compared to BF < 6 months, was associated with higher adolescent BMD z-score adjusting for covariates (β = 0.29, p < 0.05). Mixed BF was not significantly related to adolescent BMD z-score (β = 0.06, p = 0.47). For every 30 days of BF as the sole source of milk, adolescent BMD z-score increased by 0.03 (p = 0.01).

CONCLUSION

BF without formula supplementation for at least 6 months was associated with higher adolescent BMD z-score and a suggestive trend in the same direction for BMD suggests that exclusivity and duration of BF may play a role in adolescent bone health.

Infant iron deficiency, child affect, and maternal unresponsiveness: Testing the long-term effects of functional isolation

Children who are iron deficient (ID) or iron-deficient anemic (IDA) have been shown to seek and receive less stimulation from their caregivers, contributing to functional isolation. Over time, the reduced interactions between child and caregiver are thought to interfere with the acquisition of normative social competencies and adversely affect the child's development. The current study examined functional isolation in children who were ID or IDA in infancy in relation to social difficulties in middle childhood and problem behaviors in adolescence. Using a sample of 873 Chilean children, 45% of whom were ID or IDA in infancy, structural equation modeling results indicated that infant IDA was associated with children's dull affect and social reticence at age 5, which were related to mothers' unresponsiveness and understimulation. Mothers' limited responsiveness and stimulation were, in turn, related to children's peer rejection at age 10, which further linked to problem behaviors and associating with deviant peers at adolescence. Findings support the functional isolation hypothesis and suggest that early limited caregiver responsiveness and stimulation contribute to long-term social difficulties in adolescents who were iron-deficient anemic in infancy. (PsycINFO Database Record

Iron Fortification: Its Efficacy and Safety in Relation to Infections

Iron-fortification programs are efficacious and effective provided recent guidelines are followed: the iron compound is carefully chosen and its level in the food is based on target population requirements, the amount lacking in the diet, and the iron bioavailability of the diet and the compound. For monitoring, serum ferritin and transferrin receptor should be included in addition to hemoglobin. Thus, recent studies of provision of iron-fortified salt to children in Morocco, rice to children in India, wheat flour to women in Thailand, and fish sauce in Vietnam have demonstrated efficacy and effectiveness. All were in nonmalarious areas, and intestinal parasites were uncommon except in India, where the children were dewormed. C-reactive protein was used to eliminate high ferritin values due to infection. An efficacy study of iron-fortified salt in dewormed school-aged children in Côte d'Ivoire, where the prevalence of malaria parasitemia was 55%, found no change in hemoglobin after 6 months, but serum ferritin increased and transferrin receptor decreased significantly, and the increase in body iron and estimated iron absorbed compared favorably with the results of a study of similar design in Morocco, where the prevalence of iron-deficiency anemia decreased from 30% to 5% after 10 months. Hence, iron-fortification programs in malarious areas may not decrease anemia prevalence but will improve iron status and, presumably, iron-dependent health outcomes. Eight studies in nonmalarious areas, all but one in infants receiving iron-fortified formula, have found no evidence of increase in infections and some evidence of a decrease in respiratory infection. There have been no studies in malarious areas.

The Effect of Low Dose Iron and Zinc Intake on Child Micronutrient Status and Development during the First 1000 Days of Life: A Systematic Review and Meta-Analysis

Adequate supply of micronutrients during the first 1000 days is essential for normal development and healthy life. We aimed to investigate if interventions administering dietary doses up to the recommended nutrient intake (RNI) of iron and zinc within the window from conception to age 2 years have the potential to influence nutritional status and development of children. To address this objective, a systematic review and meta-analysis of randomized and quasi-randomized fortification, biofortification, and supplementation trials in women (pregnant and lactating) and children (6–23 months) delivering iron or zinc in doses up to the recommended nutrient intake (RNI) levels was conducted. Supplying iron or zinc during pregnancy had no effects on birth outcomes. There were limited or no data on the effects of iron/zinc during pregnancy and lactation on child iron/zinc status, growth, morbidity, and psychomotor and mental development. Delivering up to 15 mg iron/day during infancy increased mean hemoglobin by 4 g/L (p < 0.001) and mean serum ferritin concentration by 17.6 µg/L (p < 0.001) and reduced the risk for anemia by 41% (p < 0.001), iron deficiency by 78% (ID; p < 0.001) and iron deficiency anemia by 80% (IDA; p < 0.001), but had no effect on growth or psychomotor development. Providing up to 10 mg of additional zinc during infancy increased plasma zinc concentration by 2.03 µmol/L (p < 0.001) and reduced the risk of zinc deficiency by 47% (p < 0.001). Further, we observed positive effects on child weight for age z-score (WAZ) (p < 0.05), weight for height z-score (WHZ) (p < 0.05), but not on height for age z-score (HAZ) or the risk for stunting, wasting, and underweight. There are no studies covering the full 1000 days window and the effects of iron and zinc delivered during pregnancy and lactation on child outcomes are ambiguous, but low dose daily iron and zinc use during 6–23 months of age has a positive effect on child iron and zinc status.

Bioaccumulation of metals in common carp (Cyprinus carpio L.) from water bodies of Anatolia (Turkey): a review with implications for fisheries and human food consumption

Although fish is widely consumed by humans for its nutritional properties, accumulation of heavy metals can pose serious health hazards. Widespread common carp Cyprinus carpio is cultured worldwide and represents an economically important species for fisheries in several countries. These include Turkey, where C. carpio often makes for a large part of the sales of the locally marketed fish and also for a traditional dish. This study provides a review of bioaccumulation of metals in tissues of C. carpio from water bodies of Anatolia and also includes reference to worldwide studies. From 42 water bodies across the region, 27 metals in total were studied, of which Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were the most widely analysed, mainly in the muscle, liver and gill tissues. Amongst the potentially toxic metals, Cd, Cr and Pb occurred in several water bodies at concentrations not only above maximum allowed limits but also higher relative to other water bodies worldwide, even though As, Hg and Ni were also sometimes present at potentially hazardous concentrations. The essential metals Cu, Fe, Mn, Se and Zn were detected at various concentrations, with the latter two occasionally above limit. All water bodies flagged as having especially critical (i.e. above limit) concentrations of toxic metals supported C. carpio fisheries from highly populated regions, raising concern about food safety and calling for preventative measures. Given the significantly lower bioaccumulation levels in the muscle relative to the liver and gill tissues, it is suggested that consumption of C. carpio as fillets may be safer than after processing into e.g. meat balls and sausages. The limits of 1.0 μg/g for Cr and 1.15 μg/g for Se, currently lacking from the Turkish food safety legislation, are proposed, and it is suggested that a similar meta-analytical approach as adopted in this study may benefit other countries where C. carpio represents an important fisheries resource.

The effect of iodine supplementation in pregnancy on early childhood neurodevelopment and clinical outcomes: results of an aborted randomised placebo-controlled trial

BACKGROUND

Concern that mild iodine deficiency in pregnancy may adversely affect neurodevelopment of offspring has led to recommendations for iodine supplementation in the absence of evidence from randomised controlled trials. The primary objective of the study was to investigate the effect of iodine supplementation during pregnancy on childhood neurodevelopment. Secondary outcomes included pregnancy outcomes, maternal thyroid function and general health.

METHODS

Women with a singleton pregnancy of fewer than 20 weeks were randomly assigned to iodine (150 μg/d) or placebo from trial entry to birth. Childhood neurodevelopment was assessed at 18 months by using Bayley Scales of Infant and Toddler Development (Bayley-III). Iodine status and thyroid function were assessed at baseline and at 36 weeks' gestation. Pregnancy outcomes were collected from medical records.

RESULTS

The trial was stopped after 59 women were randomly assigned following withdrawal of support by the funding body. There were no differences in childhood neurodevelopmental scores between the iodine treated and placebo groups. The mean cognitive, language and motor scores on the Bayley-III (iodine versus placebo, respectively) were 99.4 ± 12.2 versus 101.7 ± 8.2 (mean difference (MD) -2.3, 95 % confidence interval (CI) -7.8, 3.2; P = 0.42), 97.2 ± 12.2 versus 97.9 ± 11.5 (MD -0.7, 95 % CI -7.0, 5.6; P = 0.83) and 93.9 ± 10.8 versus 92.4 ± 9.7 (MD 1.4, 95 % CI -4.0, 6.9; P = 0.61), respectively. No differences were identified between groups in any secondary outcomes.

CONCLUSIONS

Iodine supplementation in pregnancy did not result in better childhood neurodevelopment in this small trial. Adequately powered randomised controlled trials are needed to provide conclusive evidence regarding the effect of iodine supplementation in pregnancy.

TRIALS REGISTRATION

The trial was registered with the Australian New Zealand Clinical Trials Registry at http://www.anzctr.org.au . The registration number of this trial is ACTRN12610000411044 . The trial was registered on 21 May 2010.

Iron supplementation in infancy contributes to more adaptive behavior at 10 years of age

Most studies of behavioral/developmental effects of iron deficiency anemia (IDA) or iron supplementation in infancy have found social-emotional differences. Differences could relate to behavioral inhibition or lack of positive affect and altered response to reward. To determine long-term behavioral effects, the study was a follow-up of a randomized controlled trial of behavioral/developmental effects of preventing IDA in infancy. Healthy Chilean infants free of IDA at age 6 mo were randomly assigned to iron supplementation or no added iron (formula with iron/powdered cow milk, vitamins with/without iron) from ages 6 to 12 mo. At age 10 y, 59% (666 of 1123) and 68% (366 of 534) of iron-supplemented and no-added-iron groups were assessed. Social-emotional outcomes included maternal-reported behavior problems, self-reported behavior, examiner ratings, and video coding of a social stress task and gamelike paradigms. Examiners rated the iron-supplemented group as more cooperative, confident, persistent after failure, coordinated, and direct and reality-oriented in speech and working harder after praise compared with the no-added-iron group. In a task designed to elicit positive affect, supplemented children spent more time laughing and smiling together with their mothers and started smiling more quickly. In the social stress task they smiled and laughed more and needed less prompting to complete the task. All P values were <0.05; effect sizes were 0.14-0.36. There were no differences in behaviors related to behavioral inhibition, such as anxiety/depression or social problems. In sum, iron supplementation in infancy was associated with more adaptive behavior at age 10 y, especially in affect and response to reward, which may improve performance at school and work, mental health, and personal relationships.

Assessment of trace element levels in muscle tissues of fish species collected from a river, stream, lake, and sea in Sakarya, Turkey

Levels of some trace and essential elements, including Al, B, Ba, Cr, Cu, Fe, Mn, Ni, Sr, and Zn, were determined in 17 different fish species from Sakarya River, Çark Stream, Sapanca Lake, and Western Black Sea using ICP-OES after microwave (MW) digestion procedure. During preparation of samples for analysis, wet and MW digestion methods were also compared. Accuracy of the digestion methods was checked by the analysis of DORM-3 reference material (Fish Protein Certified Reference Material for Trace Metals). Concentrations of trace elements were found as Al: 6.5–48.5, B: 0.06–3.30, Ba: 0.09–2.92, Cr: 0.02–1.64, Cu: 0.13–2.28, Fe: 7.28–39.9, Mn: 0.08–11.4, Ni: 0.01–26.1, Sr: 0.17–13.5, and Zn: 11.5–52.9 µg g⁻¹. The obtained results were compared with other studies published in the literature. Trace element levels in various fish species collected from waters in Sakarya region were found to be below limit values provided by Turkish Food Codex (TFC), Food and Agriculture Organization (FAO), and World Health Organization (WHO).

Iron requirements of infants and toddlers

Iron deficiency (ID) is the most common micronutrient deficiency worldwide and young children are a special risk group because their rapid growth leads to high iron requirements. Risk factors associated with a higher prevalence of ID anemia (IDA) include low birth weight, high cow's-milk intake, low intake of iron-rich complementary foods, low socioeconomic status, and immigrant status. The aim of this position paper was to review the field and provide recommendations regarding iron requirements in infants and toddlers, including those of moderately or marginally low birth weight. There is no evidence that iron supplementation of pregnant women improves iron status in their offspring in a European setting. Delayed cord clamping reduces the risk of ID. There is insufficient evidence to support general iron supplementation of healthy European infants and toddlers of normal birth weight. Formula-fed infants up to 6 months of age should receive iron-fortified infant formula, with an iron content of 4 to 8 mg/L (0.6-1.2 mg(-1) · kg(-1) · day(-1)). Marginally low-birth-weight infants (2000-2500 g) should receive iron supplements of 1-2 mg(-1) · kg(-1) · day(-1). Follow-on formulas should be iron-fortified; however, there is not enough evidence to determine the optimal iron concentration in follow-on formula. From the age of 6 months, all infants and toddlers should receive iron-rich (complementary) foods, including meat products and/or iron-fortified foods. Unmodified cow's milk should not be fed as the main milk drink to infants before the age of 12 months and intake should be limited to <500 mL/day in toddlers. It is important to ensure that this dietary advice reaches high-risk groups such as socioeconomically disadvantaged families and immigrant families.

Motor activity and intra-individual variability according to sleep-wake states in preschool-aged children with iron-deficiency anemia in infancy

BACKGROUND

A chronic or acute insult may affect the regulatory processes that guide motor and behavioral performance, leading to increased intra-individual variability (IIV). Increased variability is often interpreted as an indication of regulatory dysfunction. Iron plays an important role in the regulatory processes of the nervous system and affects motor activity. To our knowledge, no study has examined the long-lasting patterns and IIV of motor activity following iron-deficiency anemia in human infants.

AIMS

This study compared 48-h motor activity and variability in preschool-aged children with or without iron-deficiency anemia (IDA) in infancy.

METHODS

Motor activity was recorded through actigraphs during two week-days in 47 4-year-old Chilean children (23 former IDA and 24 non-anemic in infancy). All were given oral iron as infants. Sleep-wake states were identified by means of automated software. The frequency of movement units per minute was determined for each waking/sleep state during the individual day and night periods; data were examined in blocks of 15 min. Analyses of mean frequency and duration and intra-individual variability were conducted using multivariate mixed models.

RESULTS

For daytime sleep, former IDA children were more active without a difference in the total duration. They also spent less time awake throughout the individual day period. Motor activity intra-individual variability was higher in former IDA children.

CONCLUSIONS

The findings suggest that IDA in infancy sets the stage for long lasting dysfunction in the neural processes regulating sleep-wake states and spontaneous motor activity patterns.

Satiety responsiveness and eating behavior among Chilean adolescents and the role of breastfeeding

Objective

To determine patterns of satiety responsiveness and its relationship to eating in the absence of hunger (EAH), in a cohort of adolescents. We also assessed whether sex, BMI and duration of breastfeeding, during infancy, predicted satiety responsiveness and eating behavior at 16 years.

Methods

Adolescents (n=576) from a longitudinal cohort, that began as an iron deficiency anemia preventive trial, participated in an unlimited breakfast after an overnight fast, and reported satiety response on a visual analogue scale after the meal, followed by an EAH procedure. Height, weight and body composition were measured before breakfast. Latent profile analysis generated profiles that captured individual differences in satiety responsiveness. Multivariable regressions, adjusted for potential confounders, evaluated the association between: 1) satiety responsiveness and EAH, and 2) breastfeeding in infancy, satiety responsiveness and EAH in adolescence.

Results

Participants were on average 16.7-years-old, 48% female, 37% overweight/obese and 76% were breastfed as the sole source of milk for < 6 months. We found three latent profiles of satiety responsiveness: 1. “responsive” (49%); 2. “not responsive” (41%); 3. “still hungry” (10%). Participants in the “not responsive” or “still hungry” profile were more likely to eat during the EAH procedure (OR=2.5, 95%CI 1.8–3.6). Being breastfed for < 6 months was related to higher odds of being in the “not responsive” or “still hungry” profile (OR 1.8, 95%CI 1.2–2.6) and EAH (OR=2.2, 95% CI 1.4–3.3). Satiety responsiveness was not influenced by sex and overweight/obesity.

Conclusion

After an ad libitum meal, we found varied satiety responses, which related to EAH. Furthermore, shorter breastfeeding duration was associated with poorer satiety response and higher consumption during an EAH procedure. Understanding if breastfeeding influences the development of satiety responsiveness and eating behavior may be important in an era characterized by abundant calorie-dense foods and a plethora of environmental cues promoting consumption.

Health effects of different dietary iron intakes: a systematic literature review for the 5th Nordic Nutrition Recommendations

BACKGROUND

The present literature review is part of the NNR5 project with the aim of reviewing and updating the scientific basis of the 4th edition of the Nordic Nutrition Recommendations (NNR) issued in 2004.

OBJECTIVE

The objective of this systematic literature review was to assess the health effects of different intakes of iron, at different life stages (infants, children, adolescents, adults, elderly, and during pregnancy and lactation), in order to estimate the requirement for adequate growth, development, and maintenance of health.

METHODS

The initial literature search resulted in 1,076 abstracts. Out of those, 276 papers were identified as potentially relevant. Of those, 49 were considered relevant and were quality assessed (A, B, or C). An additional search on iron and diabetes yielded six articles that were quality assessed. Thus, a total of 55 articles were evaluated. The grade of evidence was classified as convincing (grade 1), probable (grade 2), suggestive (grade 3), and inconclusive (grade 4).

RESULTS

There is suggestive evidence that prevention or treatment of iron deficiency (ID) and iron deficiency anemia (IDA) improves cognitive, motoric, and behavioral development in young children, and that treatment of IDA improves attention and concentration in school children and adult women. There is insufficient evidence to show negative health effects of iron intakes in doses suggested by the NNR 4. There is insufficient evidence to suggest that normal birth weight, healthy, exclusively breast-fed infants need additional dietary iron before 6 months of life in the Nordic countries. An iron concentration of 4-8 mg/L in infant formulas seems to be safe and effective for normal birth weight infants. There is probable evidence that iron supplements (1-2 mg/kg/day) given up to 6 months of age to infants with low birth weight (<2,500 g) prevents IDA and possibly reduce the risk of behavioral problems later on. There is probable evidence that ID and IDA in pregnant women can be effectively prevented by iron supplementation at a dose of 40 mg/day from week 18-20 of gestation. There is probable evidence that a high intake of heme iron, but not total dietary, non-heme or supplemental iron, is associated with increased risk of type 2 diabetes (T2D) and gestational diabetes.

CONCLUSIONS

Overall, the evidence does not support a change of the iron intakes recommended in the NNR 4. However, one could consider adding recommendations for infants below 6 months of age, low birth weight infants and pregnant women.

Compositional requirements of follow-up formula for use in infancy: recommendations of an international expert group coordinated by the Early Nutrition Academy

The follow-up formula (FUF) standard of Codex Alimentarius adopted in 1987 does not correspond to the recently updated Codex infant formula (IF) standard and current scientific knowledge. New Zealand proposed a revision of the FUF Codex standard and asked the non-profit Early Nutrition Academy, in collaboration with the Federation of International Societies for Paediatric Gastroenterology, Hepatology, and Nutrition (FISPGHAN), for a consultation with paediatric nutrition experts to provide scientific guidance. This global expert group strongly supports breastfeeding. FUF are considered dispensable because IF can substitute for breastfeeding throughout infancy, but FUF are widely used and thus the outdated current FUF standard should be revised. Like IF, FUF serve as breast milk substitutes; hence their marketing should respect appropriate standards. The compositional requirements for FUF for infants from 6 months onwards presented here were unanimously agreed upon. For some nutrients, the compositional requirements for FUF differ from those of IF due to differing needs with infant maturation as well as a rising contribution of an increasingly diversified diet with advancing age. FUF should be fed with adequate complementary feeding that is also appropriate for partially breastfed infants. FUF could be fed also after the age of 1 year without safety concerns, but different compositional requirements should be applied for optimal, age-adapted milk-based formulations for young children used only after the age of 1 year. This has not been considered as part of this review and should be the subject of further consideration.

Iron status of one-year-olds and association with breast milk, cow's milk or formula in late infancy

PURPOSE

Studies on iron status in infancy and early childhood have shown contradicting results concerning prolonged breast-feeding and cow's milk intake. The aim of the present study was to investigate associations between iron status among one-year-olds and feeding, with focus on the type of milk.

METHODS

Randomly selected healthy infants were prospectively investigated until 1 year of age in two cohorts born 1995-1996 (n = 114) and 2005 (n = 140). Information on birth data, feeding and growth until 12 months and iron status at 12 months was collected. Data from the two cohorts were pooled and the infants categorized into three groups according to their predominant milk consumption at 9 months of age, that is, breast milk, cow's milk or follow-on formula.

RESULTS

The prevalence of iron deficiency was highest in the cow's milk group and lowest in the follow-on formula group. According to a linear model, adjusted for gender, birth weight and exclusive breast-feeding duration, cow's milk consumption was negatively associated with serum ferritin (SF) and formula positively, but breast milk not. Predicted SF (μg/l) = 11.652(intercept) - 5.362(boy) + 0.005 × birth weight (g) + 2.826(exclusively breastfed ≥ 4 months) + 0.027 × formula (ml) - 0.022 × cow's milk (ml) + 0.005 × breast milk (ml). Correction for other dietary factors did not change these results.

CONCLUSION

In this pooled analysis, cow's milk intake in late infancy associated negatively, and follow-on formula positively, with iron status. Prolonged partial breast-feeding does not seem to be of importance for iron status. Fortified food seems to improve iron status in late infancy.

Effect of iron-fortified foods on hematologic and biological outcomes: systematic review of randomized controlled trials

BACKGROUND

The utility of iron fortification of food to improve iron deficiency, anemia, and biological outcomes is not proven unequivocally.

OBJECTIVES

The objectives were to evaluate 1) the effect of iron fortification on hemoglobin and serum ferritin and the prevalence of iron deficiency and anemia, 2) the possible predictors of a positive hemoglobin response, 3) the effect of iron fortification on zinc and iron status, and 4) the effect of iron-fortified foods on mental and motor development, anthropometric measures, and infections.

DESIGN

Randomized and pseudorandomized controlled trials that included food fortification or biofortification with iron were included.

RESULTS

Data from 60 trials showed that iron fortification of foods resulted in a significant increase in hemoglobin (0.42 g/dL; 95% CI: 0.28, 0.56; P < 0.001) and serum ferritin (1.36 μg/L; 95% CI: 1.23, 1.52; P < 0.001), a reduced risk of anemia (RR: 0.59; 95% CI: 0.48, 0.71; P < 0.001) and iron deficiency (RR: 0.48; 95% CI: 0.38, 0.62; P < 0.001), improvement in other indicators of iron nutriture, and no effect on serum zinc concentrations, infections, physical growth, and mental and motor development. Significant heterogeneity was observed for most of the evaluated outcomes. Sensitivity analyses and meta-regression for hemoglobin suggested a higher response with lower trial quality (suboptimal allocation concealment and blinding), use of condiments, and sodium iron edetate and a lower response when adults were included.

CONCLUSION

Consumption of iron-fortified foods results in an improvement in hemoglobin, serum ferritin, and iron nutriture and a reduced risk of remaining anemic and iron deficient.

Effects of micronutrient fortified milk and cereal food for infants and children: a systematic review

BACKGROUND

Micronutrient deficiency is a common public health problem in developing countries, especially for infants and children in the first two years of life. As this is an important time window for child development, micronutrient fortified complementary feeding after 6 months of age, for example with milk or cereals products, in combination with continued breastfeeding, is recommended. The overall effect of this approach is unclear.

METHODS

We performed a Systematic Review and Meta-analysis to assess the impact of micronutrient fortified milk and cereal food on the health of infants and little children (aged 6 months to 5 years) compared to non-fortified food. We reviewed randomized controlled trials using electronic databases (MEDLINE and Cochrane library searches through FEB 2011), reference list screening and hand searches. Three reviewers assessed 1153 studies for eligibility and extracted data. One reviewer assessed risk of bias using predefined forms.

RESULTS

We included 18 trials in our analysis (n = 5'468 children; range of mean hemoglobin values: 9.0 to 12.6 g/dl). Iron plus multi micronutrient fortification is more effective than single iron fortification for hematologic outcomes. Compared to non-fortified food, iron multi micronutrient fortification increases hemoglobin levels by 0.87 g/dl (95%-CI: 0.57 to 1.16; 8 studies) and reduces risk of anemia by 57% (relative risk 0.43; 95%-CI 0.26 to 0.71; absolute risk reduction 22%; number needed to treat 5 [95%-CI: 4 to 6]; 6 Studies). Compared to non-fortified food, fortification increases serum levels of vitamin A but not of zinc. Information about functional health outcomes (e.g. weight gain) and morbidity was scarce and evidence is inconclusive. Risk of bias is unclear due to underreporting, but high quality studies lead to similar results in a sensitivity analysis.

CONCLUSIONS

Multi micronutrient fortified milk and cereal products can be an effective option to reduce anemia of children up to three years of age in developing countries. On the basis of our data the evidence for functional health outcomes is still inconclusive.

Iron-fortified vs low-iron infant formula: developmental outcome at 10 years

OBJECTIVE

To assess long-term developmental outcome in children who received iron-fortified or low-iron formula.

DESIGN

Follow-up at 10 years of a randomized controlled trial (1991-1994) of 2 levels of formula iron. Examiners were masked to group assignment.

SETTING

Urban areas around Santiago, Chile.

PARTICIPANTS

The original study enrolled healthy, full-term infants in community clinics; 835 completed the trial. At 10 years, 473 were assessed (56.6%).

INTERVENTION

Iron-fortified (mean, 12.7 mg/L) or low-iron (mean, 2.3 mg/L) formula from 6 to 12 months.

MAIN OUTCOME MEASURES

We measured IQ, spatial memory, arithmetic achievement, visual-motor integration, visual perception, and motor functioning. We used covaried regression to compare iron-fortified and low-iron groups and considered hemoglobin level before randomization and sensitivity analyses to identify 6-month hemoglobin levels at which groups diverged in outcome.

RESULTS

Compared with the low-iron group, the iron-fortified group scored lower on every 10-year outcome (significant for spatial memory and visual-motor integration; suggestive for IQ, arithmetic achievement, visual perception, and motor coordination; 1.4-4.6 points lower; effect sizes, 0.13-0.21). Children with high 6-month hemoglobin levels (> 12.8 g/dL [to convert to grams per liter, multiply by 10]) showed poorer outcome on these measures if they received iron-fortified formula (10.7-19.3 points lower; large effect sizes, 0.85-1.36); those with low hemoglobin levels (< 10.5 g/dL) showed better outcome (2.6-4.5 points higher; small but significant effects, 0.22-0.36). High hemoglobin levels represented 5.5% of the sample (n = 26) and low hemoglobin levels represented 18.4% (n = 87).

CONCLUSION

Long-term development may be adversely affected in infants with high hemoglobin levels who receive 12.7 mg/L of iron-fortified formula. Optimal amounts of iron in infant formula warrant further study.

Randomized controlled trial of iron-fortified drinking water in preschool children

OBJECTIVES

To evaluate the effects of fortified drinking water, with different concentrations of iron added, on hemoglobin and hematocrit values in preschoolers.

METHODS

Double-blind, randomized cluster clinical trial, with children aged 2 to 5 years of age, from 4 state-run schools, forming 1 group for each school. For fortification, ferrous sulphate in concentrations of 5 mg of elemental iron per liter of water (group A), 7.5 mg (group B), and 10 mg (group C), was used during a period of 4 months. In group D, the control, a placebo (Bixa orellana) was added. Hemoglobin and hematocrit values were checked before and after intervention.

RESULTS

Before fortification, hemoglobin and hematocrit averages were below the reference values adopted in all groups. After fortification, the prevalence of anemia showed a reduction in the 4 groups, which was more pronounced in group B, at 48.3%. The hemoglobin values in groups B (11.5) and C (11.4) were statistically similar. However, the average consumption of water/day/student was lower in group C. Comparison of hemoglobin values between groups A (11.2) and D (11.0) did not show a significant difference, suggesting insignificant efficacy with 5 mg Fe/L fortification.

CONCLUSIONS

The consumption of drinking water fortified with 7.5 mg of elemental iron/L water resulted in greater adhesion and an increase in hemoglobin values, with a reduction in the prevalence of anemia.

Diagnosis and prevention of iron deficiency and iron-deficiency anemia in infants and young children (0-3 years of age)

This clinical report covers diagnosis and prevention of iron deficiency and iron-deficiency anemia in infants (both breastfed and formula fed) and toddlers from birth through 3 years of age. Results of recent basic research support the concerns that iron-deficiency anemia and iron deficiency without anemia during infancy and childhood can have long-lasting detrimental effects on neurodevelopment. Therefore, pediatricians and other health care providers should strive to eliminate iron deficiency and iron-deficiency anemia. Appropriate iron intakes for infants and toddlers as well as methods for screening for iron deficiency and iron-deficiency anemia are presented.

Home intervention improves cognitive and social-emotional scores in iron-deficient anemic infants

BACKGROUND

Iron-deficiency anemia (IDA) is associated with alterations in infant behavior and development that may not be corrected with iron therapy.

OBJECTIVE

To determine if a home-based intervention to foster child development improves behavior and development of infants with IDA.

METHODS

Infants with IDA and nonanemic infants aged 6 and 12 months were treated with oral iron and randomly assigned to a year of surveillance or intervention. Infants in the surveillance group were visited weekly, and information on iron intake, feeding, and health were recorded. Infants in the intervention were visited weekly, and the home visits included an hour-long program to foster child development by providing support to the mother-infant relationship. The number of infants enrolled was 128 (66 who received intervention) and 149 (70 intervention) at 6 and 12 months, respectively. Psychologists who were unaware of iron status and intervention assignment assessed infants' cognitive, motor, and social-emotional development (Bayley Scales) at the beginning, midpoint, and end of the year; 116 6-month-olds and 134 12-month-olds had at least 2 assessments. Hierarchical linear modeling was used to analyze change over time.

RESULTS

Infants with IDA, regardless of enrollment age, were rated as less positive in social-emotional behavior at baseline. There were significant interactions between iron status and intervention associated with change in cognitive performance and positive social-emotional behavior. Infants with IDA who received intervention had developmental trajectories comparable to those of nonanemic infants in the intervention and surveillance groups, but these infants did not catch up in social-emotional behavior. Infants with IDA who received surveillance showed less increase in cognitive scores and had declines in positive social-emotional ratings.

CONCLUSIONS

Home-based intervention to foster child development improved cognitive and social-emotional scores in infants with IDA, but social-emotional differences remained between infants with IDA and those without IDA.

Growth and micronutrient status in children receiving a fortified complementary food

Linear growth retardation and anemia are the most prevalent nutritional problems in the world; effective interventions are urgently needed. We evaluated Ecuador's National Food Nutrition Program (PANN 2000) that included a micronutrient-fortified complementary food (FCF), Mi Papilla, in poor periurban and rural communities of Ecuador. The program is preventive and targeted to all infants and young children living in poor communities and receiving government health services. We compared dietary intake, micronutrient status, and growth over 11 mo in a cohort of children from the catchment areas of the PANN 2000 with same-age control children in nearby communities eligible to enter the program 1 y later. PANN 2000 children enrolled in the program when they were age 9-14 mo and were age 20-25 mo at the final survey. They consumed significantly more energy, protein, fat, iron, zinc, vitamin A, and calcium than control children because of their FCF consumption. Anemia, 76% in both groups at baseline, fell to 27% in PANN 2000 children but only to 44% in control children (P < 0.001). The odds of being anemic were 58% lower for PANN 2000 children (P = 0.003). The effects on linear growth and weight were limited to children who were older when the program began (12-14 mo) and were significant for weight (interaction with age, 0.38 kg; P = 0.029) and positive but not significant for length (0.66 cm; P = 0.08). An FCF, including ferrous sulfate, delivered through public health services, is highly effective in improving weight and hemoglobin and reducing anemia.

Iron fortification of infant formula

The purpose of this review is to examine the need for and appropriate level of Fe fortification of infant formula, and to assess any adverse effects of Fe fortification. The appropriate level of Fe fortification of infant formula has been established through studies of Fe absorption or erythrocyte incorporation of Fe, and through clinical trials of formulas with varying levels of Fe that were aimed at preventing the development of Fe deficiency in participating infants. In addition, the effects of varying levels of Fe fortification on the absorption of other minerals and trace elements, and on the incidence of infection and immune function have been studied, as has the effect of adding bovine lactoferrin to formula. Studies of Fe absorption have shown that increasing the level of Fe fortification in formula does not significantly increase the amount absorbed, and that the addition of bovine lactoferrin is unlikely to further increase absorption of Fe. Quite different recommendations for the level of Fe fortification of formula are made in the USA and in Europe. The higher level (12 mg/l) commonly used in the USA is not well supported by the evidence from clinical trials that suggest that lower levels (4 mg/l or less) may be adequate to prevent the development of Fe deficiency. Higher levels of Fe fortification may also interfere with the absorption of other minerals such as Cu and Se. Concerns about potential adverse effects of Fe fortification on immune function and susceptibility to infections have been disproved as have concerns about associated gastrointestinal symptomatology. There are no clearly demonstrated advantages in using ‘follow-on’ formula with high Fe content (up to 13 mg/l) instead of the standard UK formulas with Fe fortification in the range 4–7 mg/l after the age of 6 months, although they may provide an important ‘safety net’ for the prevention of Fe deficiency in communities with weaning diets low in Fe.

A multicenter community study on the efficacy of double-fortified salt

BACKGROUND

Iron and iodine deficiencies affect more than 30% of the world's population. Typical Indian diets contain adequate amounts of iron, but the bioavailability is poor. This serious limiting factor is caused by low intake of meat products rich in heme iron and intake of phytates in staple foods in the Indian diet, which inhibits iron absorption.

OBJECTIVE

To test the stability of double-fortified salt (DFS) during storage and to assess its efficacy in improving the iron and iodine status of the communities.

METHODS

The stability of both iodized salt and DFS during storage for a 2-year period was determined. The bioefficacy of DFS was assessed in communities covering three states of the country for a period of 1 year. This was a multicenter, single-blind trial covering seven clusters. The experimental group used DFS and the control group used iodized salt. The salts were used in all meals prepared for family members, but determination of hemoglobin by the cyanmethemoglobin method was performed in only two or three members per family, and not in children under 10 years of age (n = 393 and 436 in the experimental and control groups, respectively). The family size was usually four or five, with a male: female ratio of 1:1, consisting of two parents with two or three children. Hemoglobin was measured at baseline, 6 months (midpoint), and 12 months (endpoint). Urinary iodine was measured in only one cluster at baseline and endpoint. All the participants were dewormed at baseline, 6 months, and 12 months.

RESULTS

The iron and iodine in the DFS were stable during storage for 2 years. Over a period of 1 year, there was an increase of 1.98 g/dL of hemoglobin in the experimental group and 0.77 g/dL of hemoglobin in the control group; the latter increase may have been due to deworming. The median urinary iodine changed from 200 microg/dL at baseline to 205 microg/dL at the end of the study in the experimental group and from 225 microg/dL to 220 microg/dL in the control group. There was a statistically significant (p < .05) improvement in the median urinary iodine status of subjects who were iodine deficient (urinary iodine < 100 microg/L) in both the experimental and the control groups, a result showing that DFS was as efficient as iodized salt in increasing urinary iodine from a deficient to sufficient status. There was a statistically significant increase (p < .05) in hemoglobin in all seven clusters in the experimental group compared with the control.

CONCLUSIONS

The iron and iodine in the DFS are stable in storage for 2 years. The DFS has proved beneficial in the delivery of bioavailable iron and iodine.