Prevention of anaemia in inner city toddlers by an iron supplemented cows' milk formula

The Potential of Iodine and Iron Double-Fortified Salt Compared with Iron-Fortified Staple Foods to Increase Population Iron Status

The potential of double-fortified salt (DFS) to improve population iron status is compared with the potential of iron-fortified wheat flour, maize flour, rice grains, and milk products. The potential for a positive impact on iron status is based on reported efficacy studies, consumption patterns, the extent of industrialization, and whether there are remaining technical issues with the fortification technologies. Efficacy studies with DFS, and with iron-fortified wheat flour, maize flour, and rice, have all reported good potential to improve population iron status. Iron-fortified milk powder has shown good impact in young children. When these foods are industrially fortified in modern, automated facilities, with high-level quality control and assurance practices, high-quality raw materials, and a wide population coverage, all vehicles have good potential to improve iron status. Relative to other fortification vehicles, fortification practices with wheat flour are the most advanced and iron-fortified wheat flour has the highest potential for impact in the short- to medium-term in countries where wheat flour is consumed as a staple. Liquid milk has the least potential, mainly because an acceptable iron fortification technology has not yet been developed. Maize is still predominantly milled in small-scale local mills and, although the extruded rice premix technology holds great promise, it is still under development. Salt has a proven record as an excellent vehicle for iodine fortification and has demonstrated good potential for iron fortification. However, technical issues remain with DFS and further studies are needed to better understand and avoid color formation and iron-catalyzed iodine losses in both high- and low-quality salts under different storage conditions. There is currently a risk that the introduction of DFS may jeopardize the success of existing salt iodization programs because the addition of iron may increase iodine losses and cause unacceptable color formation.

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.

Very low prevalence of iron deficiency among young French children: A national cross-sectional hospital-based survey

Although iron deficiency (ID) is considered the most frequent micronutrient deficiency in industrialized countries and is associated with impaired neurodevelopment when occurring in early years, accurate recent estimations of its prevalence are lacking. Our objective was to estimate ID prevalence and associated sociodemographic markers in young children in France. The Saturn-Inf national cross-sectional hospital-based survey recruited 3,831 French children <6 years old between 2008 and 2009 to assess lead poisoning prevalence and to establish a biobank. This secondary analysis measured serum ferritinemia (SF) in sera kept frozen at -80 °C for children with sufficient serum aliquots and C-reactive protein <10 mg/L. For the 657 participating children (17% of the Saturn-Inf study), the median age was 3.9 years (interquartile range: 2.2-5.1); 52% were boys. The median SF was 44 μg/L (interquartile range: 28-71). ID prevalence was 2.8% (95% confidence interval [1.7, 4.7]) and 3.2% (95% confidence interval [2.0, 5.1]) with an SF threshold of 10 and 12 μg/L, respectively. Low SF was significantly associated (p < .05) with mother being a migrant (32 vs. 45 μg/L for a mother born in France) or unemployed (37 vs. 50 μg/L for a mother employed). In this first national cross-sectional hospital-based study in France, ID prevalence was much lower than that in other French and European studies performed in underprivileged populations but close to the lowest values observed in other population-based studies in Europe.

A micronutrient-fortified young-child formula improves the iron and vitamin D status of healthy young European children: a randomized, double-blind controlled trial

BACKGROUND

Iron deficiency (ID) and vitamin D deficiency (VDD) are common among young European children because of low dietary intakes and low compliance to vitamin D supplementation policies. Milk is a common drink for young European children. Studies evaluating the effect of milk fortification on iron and vitamin D status in these children are scarce.

OBJECTIVE

We aimed to investigate the effect of a micronutrient-fortified young-child formula (YCF) on the iron and vitamin D status of young European children.

DESIGN

In this randomized, double-blind controlled trial, healthy German, Dutch, and English children aged 1-3 y were allocated to receive either YCF (1.2 mg Fe/100 mL; 1.7 μg vitamin D/100 mL) or nonfortified cow milk (CM) (0.02 mg Fe/100 mL; no vitamin D) for 20 wk. Blood samples were taken before and after the intervention. The primary and secondary outcomes were change from baseline in serum ferritin (SF) and 25-hydroxyvitamin D [25(OH)D], respectively. ID was defined as SF <12 μg/L in the absence of infection (high-sensitivity C-reactive protein <10 mg/L) and VDD as 25(OH)D <50 nmol/L. Statistical adjustments were made in intention-to-treat analyses for sex, country, age, baseline micronutrient status, and micronutrient intake from food and supplements (and sun exposure in the case of vitamin D outcomes).

RESULTS

The study sample consisted of 318 predominantly Caucasian (∼95%) children. The difference in the SF and 25(OH)D change between the treatment groups was 6.6 μg/L (95% CI: 1.4, 11.7 μg/L; P = 0.013) and 16.4 nmol/L (95% CI: 9.5, 21.4 nmol/L; P < 0.001), respectively. The probability of ID (OR 0.42; 95% CI:0.18, 0.95; P = 0.036) and VDD (OR 0.22; 95% CI: 0.01, 0.51; P < 0.001) after the intervention was lower in the YCF group than in the CM group.

CONCLUSION

Micronutrient-fortified YCF use for 20 wk preserves iron status and improves vitamin D status in healthy young children in Western Europe. This trial was registered at www.trialregister.nl as NTR3609.

Effect of fortified milk on growth and nutritional status in young children: a systematic review and meta-analysis

Objective

Adequate nutrition is critical for optimal growth and development. However, young children may be at risk of nutrient deficiencies when transitioning to weaning foods for a variety of reasons. Supplementation with fortified milk may provide potentially lacking essential nutrients, but effects on growth and nutritional status are yet to be established.

Design

Five databases were searched for randomised controlled trials using fortified milk against control milk in young children. Outcomes were growth, body composition and/or biochemical markers. Pooled differences in means were calculated for continuous outcomes and odds ratios for binary outcomes.

Setting

Randomised controlled trials set in any country.

Subjects

Otherwise healthy children aged 6–47 months.

Results

Fifteen articles met the eligibility criteria. Fortification varied from Fe, Zn, vitamins, essential fatty acids, to pre- and/or probiotics. Frequently reported outcomes were weight, height and Fe status. Studies varied in geographical location, sample size and duration. Fortified milk had minimal effects on weight gain (mean difference=0·17 kg; 95 % CI 0·02, 0·31 kg) compared with control milk. The risk of anaemia was reduced in fortified milk groups (OR=0·32; 95 % CI 0·15, 0·66) compared with control groups. There were no significant effects on height gain, changes in body composition or Hb concentration.

Conclusions

Fortified milk is an effective source of complementary nutrition to supplement children in need when consumed in appropriate amounts in addition to a normal diet. Due to compositional differences, further research on fortified milk is warranted before making global recommendations on benefits for growth and nutritional outcomes in young children.

Mode of oral iron administration and the amount of iron habitually consumed do not affect iron absorption, systemic iron utilisation or zinc absorption in iron-sufficient infants: a randomised trial

Different metabolic pathways of supplemental and fortification Fe, or inhibition of Zn absorption by Fe, may explain adverse effects of supplemental Fe in Fe-sufficient infants. We determined whether the mode of oral Fe administration or the amount habitually consumed affects Fe absorption and systemic Fe utilisation in infants, and assessed the effects of these interventions on Zn absorption, Fe and Zn status, and growth. Fe-sufficient 6-month-old infants (n 72) were randomly assigned to receive 6·6 mg Fe/d from a high-Fe formula, 1·3 mg Fe/d from a low-Fe formula or 6·6 mg Fe/d from Fe drops and a formula with no added Fe for 45 d. Fractional Fe absorption, Fe utilisation and fractional Zn absorption were measured with oral (57Fe and 67Zn) and intravenous (58Fe and 70Zn) isotopes. Fe and Zn status, infection and growth were measured. At 45 d, Hb was 6·3 g/l higher in the high-Fe formula group compared with the Fe drops group, whereas serum ferritin was 34 and 35 % higher, respectively, and serum transferrin 0·1 g/l lower in the high-Fe formula and Fe drops groups compared with the low-Fe formula group (all P<0·05). No intervention effects were observed on Fe absorption, Fe utilisation, Zn absorption, other Fe status indices, plasma Zn or growth. We concluded that neither supplemental or fortification Fe nor the amount of Fe habitually consumed altered Fe absorption, Fe utilisation, Zn absorption, Zn status or growth in Fe-sufficient infants. Consumption of low-Fe formula as the only source of Fe was insufficient to maintain Fe stores.

Decline in the prevalence of anaemia among children of pre-school age after implementation of wheat flour fortification with multiple micronutrients in Jordan

Objective

To examine changes in the prevalence of anaemia and its correlates among children of pre-school age after implementation of wheat flour fortification with multiple micronutrients in Jordan.

Design

Retrospective analysis of the data from two repeated national cross-sectional panels of pre-school children.

Setting

The two surveys were conducted in 2007 and 2009, 16–20 months and 34–36 months, respectively, after implementation of wheat flour fortification with multiple micronutrients in Jordan. Anaemia was considered if Hb level was <11 g/dl. An anaemia prevalence of ≥40 % was considered a severe public health problem, while that of 20–39·9 % was considered a moderate public health problem.

Subjects

A total of 3789 and 3447 children aged 6–59 months tested in 2007 and 2009, respectively.

Results

The prevalence of anaemia in pre-school children declined from 40·4 % in 2007 to 33·9 % in 2009 (adjusted OR=0·74; P<0·001). The decline in the prevalence in 2009 as compared with 2007 was more pronounced among children aged >24 months (−13·7 points), children living in urban areas (−8·0 points), children from rich households (−9·0 points), children who had never been breast-fed (−17·0 points) and well-nourished children (−6·8 points). In both surveys, presence of childhood anaemia was strongly associated with child age ≤24 months, living in poor households, breast-feeding for ≥6 months, malnourishment, poor maternal education and maternal anaemia.

Conclusions

The public health problem of childhood anaemia declined from severe in 2007 to moderate in 2009, after the implementation of wheat flour fortification with multiple micronutrients in Jordan.

Health effects of cow’s milk consumption in infants up to 3 years of age: a systematic review and meta-analysis

Objective

To summarize the best available evidence regarding the short- and long-term health effects of cow’s milk intake in healthy, full-term infants up to 3 years of age.

Design

We conducted a systematic review and meta-analysis.

Setting

We searched MEDLINE (via PubMed), EMBASE and the Cochrane Library between 1960 and July 2013 and manually reviewed reference lists of pertinent articles. Two researchers independently reviewed abstracts and full-text articles and extracted relevant data.

Subjects

We included (randomized/non-randomized) controlled trials and observational studies.

Results

We included data from twenty-three studies (one randomized controlled trial, four non-randomized controlled trials, eight case–control studies and ten cohort studies) for the evidence synthesis. Pooled results of four studies revealed a higher risk of Fe-deficiency anaemia for infants consuming cow’s milk compared with those consuming follow-on formula (relative risk=3·76; 95 % CI 2·73, 5·19). For type 1 diabetes mellitus, six out of seven case–control studies did not show a difference in the risk of developing this disease based on the age of introduction of cow’s milk. We did not find negative associations for other health effects.

Conclusions

Cow’s milk consumption in infancy is associated with an increased risk of developing Fe-deficiency anaemia. Limiting cow’s milk consumption may be important to ensure an adequate Fe intake for infants and toddlers. High-quality patient information for caregivers is needed on how infants’ Fe requirements can be met.

Screening and routine supplementation for iron deficiency anemia: a systematic review

BACKGROUND AND OBJECTIVES

Supplementation and screening for iron-deficiency anemia (IDA) in young children may improve growth and development outcomes. The goal of this study was to review the evidence regarding the benefits and harms of screening and routine supplementation for IDA for the US Preventive Services Task Force.

METHODS

We searched Medline and Cochrane databases (1996-August 2014), as well as reference lists of relevant systematic reviews. We included trials and controlled observational studies regarding the effectiveness and harms of routine iron supplementation and screening in children ages 6 to 24 months conducted in developed countries. One author extracted data, which were checked for accuracy by a second author. Dual quality assessment was performed.

RESULTS

No studies of iron supplementation in young children reported on the diagnosis of neurodevelopmental delay. Five of 6 trials sparsely reporting various growth outcomes found no clear benefit of supplementation. After 3 to 12 months, Bayley Scales of Infant Development scores were not significantly different in 2 trials. Ten trials assessing iron supplementation in children reported inconsistent findings for hematologic measures. Evidence regarding the harms of supplementation was limited but did not indicate significant differences. No studies assessed the benefits or harms of screening or the association between improvement in impaired iron status and clinical outcomes. Studies may have been underpowered, and control factors varied and could have confounded results.

CONCLUSIONS

Although some evidence on supplementation for IDA in young children indicates improvements in hematologic values, evidence on clinical outcomes is lacking. No randomized controlled screening studies are available.

A Belgian consensus-statement on growing-up milks for children 12-36 months old

Growing-up milks (GUM) are milk-based drinks with low protein and added minerals and vitamins intended for children 12-36 months. Since the advantages of GUM are heavily debated, we reviewed the literature. A literature search was done using the classic databases (Pubmed, Embase, Cochrane) on the use of GUM in 12- to 36-month-old young children. Only limited data are available. GUM have a highly variable composition as their marketing is not regulated. Nevertheless, all papers conclude that GUM help to cover nutritional requirements of 12- to 36-month-old infants.

CONCLUSION

Appropriate intakes of macro- and micronutrients in 1- to 3-year-old children have long-term health benefits. Present diets offered to toddlers do in general not meet the requirements. Supplemented foods are therefore helpful, of which GUM is a possibility.

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.

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.

Food-based strategies improve iron status in toddlers: a randomized controlled trial12

BACKGROUND

Nonanemic iron deficiency is common in toddlers in developed countries. Food-based strategies are safe methods to control and prevent mild micronutrient deficiencies.

OBJECTIVE

Our objective was to determine the efficacy of an increased intake of red meat, or the consumption of iron-fortified milk, in improvement of iron status in toddlers at a population level.

DESIGN

In this 20-wk randomized placebo-controlled trial, 225 healthy nonanemic 12-20-mo-old children were assigned to 1 of 3 groups: red meat (toddlers encouraged to consume approximately 2.6 mg iron from red meat dishes daily), fortified milk [toddlers' regular milk replaced with iron-fortified (1.5 mg iron/100 g prepared milk) cow milk], or control [toddlers' regular milk replaced with nonfortified (0.01 mg iron/100 g prepared milk) cow milk]. Blood samples were collected at baseline and at 20 wk for hemoglobin, serum ferritin, serum transferrin receptor, and C-reactive protein. The prevalence of suboptimal iron status (ie, depleted iron stores, iron-deficient erythropoiesis, and iron deficiency anemia) was determined, and body iron was calculated.

RESULTS

No intervention effects were shown on the prevalence of suboptimal iron status. Serum ferritin increased by 44% (95% CI: 14%, 82%; P = 0.002) in the fortified milk group, did not change (+10%) in the red meat group (95% CI: -7%, 30%; P = 0.241), and tended to decrease (-14%) in the control group (95% CI: -27%, 1%; P = 0.063). By 20 wk, in comparison with the control group, serum ferritin and body iron were significantly higher in the fortified milk group (both P < 0.001), and serum ferritin was significantly higher in the red meat group (P = 0.033).

CONCLUSIONS

Consumption of iron-fortified milk can increase iron stores in healthy nonanemic toddlers, whereas increased intakes of red meat can prevent their decline. This trial was registered at actr.org.au as ACTRN12605000487617.

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.

Dietary intake and anthropometric status differ for anaemic and non-anaemic rural South African infants aged 6-12 months

The study was undertaken to determine anthropometric measurements, sociodemographic data, and dietary intake of 238 anaemic and 241 non-anaemic rural South African infants aged 6-12 months. Logistic regression with anaemia as a dependent variable showed an odds ratio (OR) of 1.89 (95% confidence interval [CI] 1.01-3.52) for low birth-weight, 2.04 (CI 1.29-3.22) for maternal age 20 years or younger, 2.21 (CI 1.29-3.76) for consumption of tea, and 0.40 (CI 0.26-0.63) for formula feeding. The anaemic infants, aged 6- < 9 months, had a lower average weight gain per month than the non-anaemic infants (727 g vs 772 g; p = 0.040, analysis of variance). Logistic regression with underweight as a dependent variable showed an OR of 3.55 (CI 1.26-10.01) for anaemia, and with stunting as a dependent variable, the OR was 2.71 (CI 1.46-5.02). Low birth-weight, a young mother aged 20 years or younger, and consumption of tea were identified as risk factors for anaemia, while formula feeding was shown to have a protective effect. The anaemic infants were more likely to show growth faltering.

Effect of iron supplementation on physical growth in children: systematic review of randomised controlled trials

OBJECTIVE

To evaluate the effect of iron supplementation on physical growth in children through a systematic review of randomised controlled trials (RCTs).

DATA SOURCES

Electronic databases, personal files, and hand search of reviews, bibliographies of books, abstracts and proceedings of international conferences.

REVIEW METHODS

RCTs evaluating change in anthropometry with interventions that included oral or parenteral iron supplementation, or iron-fortified formula milk or cereals, were analysed.

RESULTS

Twenty-five trials (26 cohorts) had relevant information. There was no evidence of publication bias. The pooled estimates (random effects model) did not document a statistically significant (P>0.05) positive effect of iron supplementation on any anthropometric variable (weight-for-age, weight-for-height, height-for-age, mid upper-arm circumference, skinfold thickness, head circumference). Significant heterogeneity was evident, and its predictors included greater weight-for-age in supplemented children in malaria hyperendemic regions and greater weight-for-height for children above 5 years of age, but a negative effect on linear growth in developed countries and with supplementation for 6 months or longer.

CONCLUSIONS

This review did not document a positive effect of iron supplementation on the physical growth of children. The identified predictors of heterogeneity should be considered as exploratory and requiring confirmation, not conclusive.

Prevalence, consequences and prevention of childhood nutritional iron deficiency: a child public health perspective

The true extent of nutritional iron deficiency (ID) in childhood is unclear because of uncertainty over its definition and the insensitivity of markers of ID. The major cause is likely to be the excessive and early use of cow's milk. Recent neurophysiological observations support the many field studies correlating ID with cognitive developmental delays. Prevention is best sought through supplementation of essential foods.

Trends in diagnosis and management of iron deficiency during infancy and early childhood

Iron deficiency remains a public health challenge. The neurocognitive deficits that are associated with iron deficiency are most worrisome. Moreover, iron deficiency-associated elevated blood lead levels magnify the problem. Pediatricians must strive to prevent iron deficiency.

The diagnosis of borderline iron deficiency: results of a therapeutic trial

BACKGROUND

Iron deficiency is common in early childhood and has been associated with developmental delay. It is not known how reliably markers of iron deficiency identify true iron deficiency, defined as a therapeutic response to oral iron.

METHODS

The subjects were members of the Millennium Baby Study cohort. At age 13 months a venous blood sample was taken for mean cell volume (MCV), haemoglobin, mean cell haemoglobin (MCH), ferritin, and zinc protoporphyrin (ZPP). Children with abnormal values were offered treatment with oral iron and dietary modification, and re-sampled after 3 months.

RESULTS

Samples were obtained for 462 children. All markers were moderately correlated with each other except ferritin. Treatment was offered to 147 (32%) children with at least one abnormal value, of whom 126 (86%) were re-sampled. Children with a haemoglobin or an MCH below the screening cut off, or with abnormal values for two or more of the remaining three measures, showed a large therapeutic response to iron, but isolated abnormalities of MCV, ZPP, or ferritin were not consistently associated with a response. Of the screened population 13% could be defined as iron deficient (abnormal haemoglobin or MCH, or abnormal levels of two or more of the remaining three markers), but this was not strongly associated with any dietary, demographic, or anthropometric characteristic.

CONCLUSIONS

Low total or mean cell haemoglobin in isolation is a specific marker of iron deficiency, but other markers are only predictive when found in combination with other abnormal values.

Iron deficiency and risk factors for lower iron stores in 6–24-month-old New Zealanders

OBJECTIVES

To determine the prevalence of biochemical iron deficiency and identify factors associated with ferritin levels among 6-24-month-old urban South Island New Zealand children.

DESIGN

Cross-sectional survey conducted from May 1998 to March 1999.

SETTING

The cities of Christchurch, Dunedin and Invercargill.

SUBJECTS

A total of 323 randomly selected 6-24-month-old children participated (response rate 61%) of which 263 provided a blood sample.

METHODS

A complete blood cell count, zinc protoporphyrin, serum ferritin and C-reactive protein were measured on nonfasting venipuncture blood samples, 3-day weighed food records and general questionnaire data were collected.

RESULTS

Among children with C-reactive protein<10 mg/l (n=231), 4.3% had iron deficiency anaemia, 5.6% had iron deficiency without anaemia, and 18.6% had depleted iron stores, when a ferritin cutoff of < or =12 g/l was used. Age (negative), sex (girls>boys), ethnicity (Caucasian>non-Caucasian), weight-for-age percentiles (negative) and birth weight (positive) were associated with ferritin after adjusting for infection and socioeconomic status. When current consumption of iron fortified formula and >500 ml of cows' milk per day were included, these were associated with a 22% increase and 25% decrease in ferritin, respectively (R2=0.28).

CONCLUSIONS

The presence of suboptimal iron status (29%) among young New Zealand children is cause for concern, even though severe iron deficiency is rare, because children with marginal iron status are at risk of developing severe iron deficiency if exposed to a physiological challenge.

Nutrition intervention in ethnic minority groups

Development of effective intervention strategies to meet the needs of people with ethnic minority origins is dependent on two factors: an understanding of the modifiable risk factors which can form the basis of intervention; an understanding of the relevant health behaviours so that appropriate strategies can be designed. The present paper briefly reviews the evidence concerning the part that nutritional and dietary factors play in the aetiology of the observed patterns of disease in these groups and the limitations of the data as a basis for intervention. Consideration is also given to the available information concerning factors influencing health behaviour (particularly eating behaviour) and the applicability of commonly-used models of behaviour change to people of ethnic minority origin. Finally, the results of nutrition intervention programmes will be examined with a view to identifying lessons for the future.

Dietary intakes of 6-24-month-old urban South Island New Zealand children in relation to biochemical iron status

OBJECTIVE

To investigate food sources and intakes of iron, and dietary factors associated with serum ferritin levels in 6-24-month-old children.

DESIGN

A cross-sectional survey employing proportionate cluster sampling was conducted in 1998/1999. Dietary intakes were assessed using a non-consecutive 3-day weighed food record. Serum ferritin and C-reactive protein were analysed from non-fasting venepuncture blood samples and general sociodemographic data were collected.

SETTING

Cities of Christchurch, Dunedin and Invercargill, New Zealand.

SUBJECTS

Randomly selected healthy 6-24-month-old non-breast-feeding children (n = 226).

RESULTS

Total iron intakes (+/- standard deviation (SD)) among non-breast-feeding infants (< 12 months old; n = 42) and toddlers (> or = 12 months old; n = 184) were 8.4 +/- 2.9 mg day(-1) and 5.0 +/- 2.5 mg day(-1), respectively. Fifteen per cent of infants and 66% of toddlers were at risk of inadequate iron intakes. Main sources of dietary iron were infant formula (60%) for infants and cereals (31%) for toddlers. Meat contributed on average 2% and 10% of dietary iron in the infant and toddler diets, respectively. Dietary factors positively associated with serum ferritin were intakes of iron and vitamin C, whereas intakes of calcium and dietary fibre were negatively associated. For each 1% increase in percentage of energy from iron-fortified formula concomitant with a 1% decrease from dairy products, there was a 4.2% increased odds of replete iron stores (ferritin > or = 20 microg l(-1)).

CONCLUSIONS

Toddlers were at higher risk of sub-optimal iron intakes than infants. Results suggest that a diet high in bioavailable iron is important for optimising the iron stores of young children in New Zealand.

Clinical safety of iron-fortified formulas

BACKGROUND

Iron-fortified formulas are recommended throughout infancy and are frequently used beyond, yet safety aspects have been inadequately studied. Iron could theoretically increase pro-oxidant stress, with potential adverse effects, including infection risk, and some clinicians suspect that iron-fortified formulas induce gastrointestinal disturbance.

OBJECTIVE

A planned component of a large intervention trial has been to test the hypothesis that infants receiving iron-fortified formula do not have a higher incidence of infections (primary outcome) or gastrointestinal problems (secondary outcome) than infants on low iron-formulas or cow's milk. Methods. Children (n = 493) 9 months old receiving cow's milk were recruited in 3 UK centers and randomized to: 1) cow's milk as before, 2) formula containing.9 mg/L of iron, or 3) an otherwise identical formula but containing 12 mg/L of iron. Children were followed at 3 monthly intervals and the episodes of infections, diarrhea and constipation, and general morbidity to 18 months old were recorded. Hematologic indices of iron status were determined at 18 months old.

RESULTS

Serum ferritin concentrations were increased in infants receiving iron-fortified formula but there were no intergroup differences in incidence of infection, gastrointestinal problems, or in general morbidity or weight gain.

CONCLUSIONS

We were unable to identify adverse health effects in older infants and toddlers consuming a high iron-containing formula (12 mg/L) even when used in populations with a low incidence of iron deficiency.

Iron fortified follow on formula from 9 to 18 months improves iron status but not development or growth: a randomised trial

AIMS

Iron deficiency anaemia is associated, in observational studies, with developmental disadvantage. This study tested the hypothesis that feeding iron supplemented formula from 9 to 18 months of age would improve developmental performance.

SUBJECTS AND METHODS

493 healthy children aged 9 months being fed pasteurised cows' milk were recruited from three UK centres. They were randomised to: cows' milk as before, formula containing 0.9 mg/litre iron, or formula containing 1.2 mg/litre iron, until 18 months of age. Bayley mental and psychomotor developmental indices were measured at 18 months, as were growth and haematological indices.

RESULTS

Children fed iron fortified formula had higher plasma ferritin concentrations, but there were no significant intergroup differences in development or growth.

CONCLUSIONS

There are no developmental or growth advantages in children given iron supplemented formula, but a benefit for a minority who were anaemic, or the possibility that a benefit may emerge at a later age, cannot be excluded.

An iron treatment trial in an aboriginal community: improving non-adherence

OBJECTIVE

To compare supervised vs unsupervised oral iron treatment in anaemic Aboriginal children living in a remote community with a 40% prevalence of iron deficiency anaemia.

METHODOLOGY

A randomised unblinded clinical trial in children < 6 years presenting to a remote Health Centre with anaemia. Oral iron prescribed as a daily unsupervised dose (group A) was compared to twice weekly supervised administration (group B) over 12 weeks. Parenteral iron (group C) was reserved for failure of oral treatment.

RESULTS

Only 3 of 25 children in group A responded to treatment compared to 23 of 26 children in group B (odds ratio = 7.7, 95% confidence interval 2.6-25.0). After six weeks of treatment, the mean haemoglobin rise was 0.96 g/L in group A compared to 10.9 g/L in group B and 12.4 g/L in group C. On entry to the study, 29.4% of subjects were underweight, 33.3% stunted and 35.3% microcephalic. The mean catch-up in weight/height on iron treatment over the study was only 0.28 (0.08, 0.48) Z-scores.

CONCLUSIONS

Oral iron as directly observed twice weekly treatment is superior to unsupervised therapy. In view of the poor compliance with unsupervised treatment and the high prevalence of iron deficiency anaemia (along with stunting and microcephaly) in Aboriginal children in northern Australia, we propose to undertake in partnership with communities a nutritional intervention program with a high energy weaning food fortified with micronutrients (iron, vitamin A, zinc, folate) as the most effective strategy to address these nutritional problems in the weaning period.

Iron supplemented formula milk related to reduction in psychomotor decline in infants from inner city areas: randomised study

OBJECTIVE

To compare the effect of unmodified cows' milk and iron supplemented formula milk on psychomotor development in infants from inner city areas when used as the main milk source.

DESIGN

Double blind, randomised intervention trial.

SETTING

Birmingham health centre.

SUBJECTS

100 infants, mean age 7.8 months (range 5.7 to 8.6 months), whose mothers had already elected to use unmodified cows' milk as their infant's milk source.

INTERVENTION

Changing to an iron supplemented formula milk from enrolment to 18 months of age, or continuing with unmodified cows' milk.

MAIN OUTCOME MEASURES

Developmental assessments using Griffiths scales at enrolment and at 18 and 24 months.

RESULTS

85 participants completed the trial. There were no significant differences in haemoglobin concentration between the two groups at enrolment, but by 18 months of age 33% of the unmodified cows' milk group, but only 2% of the iron supplemented group, were anaemic (P<0.001). The experimental groups had Griffiths general quotient scores that were not significantly different at enrolment, but the scores in both groups declined during the study. By 24 months the decrease in the mean scores in the unmodified cows' milk group was 14.7 whereas the decrease in the mean scores in the iron supplemented group was 9.3 (P<0.02, 95% confidence interval 0.4 to 10.4). Mean subquotient scores were considerably lower in the unmodified cows' milk group at 24 months; significantly so for personal and social scores (P<0.02, 1.2 to 16.8 [corrected]).

CONCLUSION

Replacing unmodified cows' milk with an iron supplemented formula milk up to 18 months of age in infants from inner city areas prevents iron deficiency anaemia and reduces the decline in psychomotor development seen in such infants from the second half of the first year.

A longitudinal study of iron status in children at 12, 24 and 36 months

OBJECTIVES

To assess iron status in a sample of clinically well, Caucasian children and explore the complex factors which contribute to iron deficiency during infancy.

DESIGN

Infants recruited at birth and followed longitudinally at 1, 2, 3, 4, 5, 6, 9, 12, 24 and 36 months; feeding practices and socioeconomic data recorded. Iron status assessed using venous blood at 12, 24 and 36 months.

SETTING

Baseline data recorded in the maternity unit. Follow-up visits took place in the infants' homes and blood sampling in a paediatric hospital.

SUBJECTS

Subjects comprised a mixed socioeconomic group of healthy children (n = 121). Blood samples taken from 85, 72 and 67% at 12, 24 and 36 months, respectively.

RESULTS

Prevalence of anaemia (Hb < 110 g l(-1)) in the longitudinal sample (n = 76) increased from 2.6% at age 12 months to 9.2% at 24 months, and at age 36 months (n = 70) was 8%. The most significant finding was that at age 12 months, cows' milk consumption was negatively associated with iron status. Other variables also had an influence. At both 24 and 36 months the most significant predictor of iron status was earlier iron status.

CONCLUSIONS

Infants born to anaemic mothers or mothers who smoke and infants who consume cows' milk during infancy are at increased risk of developing anaemia. Breast milk is the ideal, but for the infant who is not breast fed an iron fortified formula should be used. Advice to mothers should focus on the importance of introducing nutrient dense complementary foods, such as meat, which contains readily absorbable iron.

Iron status of Asian children aged 2 years living in England

Haemoglobin and ferritin values were analysed in blood from 1057 children, aged 2 years, of Asian parents living in England. Children who had thalassaemia trait or a current/recent infection were excluded. Twenty nine per cent of Pakistani, 25% of Bangladeshi, and 20% of Indian children had haemoglobin < 110.0 g/l. The recent national diet and nutrition survey of preschool children found a prevalence of 12% of 2 year olds with haemoglobin < 110.0 g/l. No single factor accounted for more than a small proportion of the variance in haemoglobin and ferritin values, but the most significant factors that had a negative effect on iron status included the amount of cows' milk consumed, the use of a baby bottle, and mother's place of birth being outside of the UK. Taking vitamin or iron supplements was positively associated with iron status in one or more of the three groups.

Follow-on formula in the prevention of iron deficiency: a multicentre study

Six-month-old infants were recruited at 21 centres in the UK and Ireland and randomly assigned to receive matching iron-fortified (12.3 mg/l iron) or non-fortified (1.4 mg/l iron) formula for 9 months. Infants already receiving cow's milk continued this feed. Haematological indices and iron status were evaluated at age 6 months, 9-10 months and 15 months. Four hundred and six infants entered and 302 completed the study. There were no differences between the groups for increases in weight, head circumference or length. Significant differences between the groups were observed at 15 months for haemoglobin, serum ferritin, serum iron and total iron binding capacity. Haemoglobin levels were < 110 g/l in 33% of infants fed cow's milk compared with 13% and 11% in those receiving non-iron-fortified and iron-fortified formula respectively. The corresponding figures for serum ferritin < 10 microg/l were 43%, 22% and 6%. Follow-on formula provides an acceptable vehicle for preventing iron deficiency in this vulnerable group.

Dietary education and iron deficiency anaemia in the inner city

OBJECTIVES

To assess if a dietary health education programme could be used within existing health resources to reduce the incidence of iron deficiency anaemia in an inner city population.

DESIGN

Prospective cohort study.

SETTING

Inner city areas of west and south Birmingham.

SUBJECTS

A total of 1000 children recorded on the child health computer register.

INTERVENTION

Children were recruited at birth and randomised into control and intervention groups. Families in the intervention group received specific health education information at key ages by face to face contact using a range of materials. The control group received standard health education as delivered by the health visitors at the time.

MAIN OUTCOME MEASURES

Haemoglobin estimation and iron content of the diet at 18 months of age.

RESULTS

A total of 455 children completed the study. Sixty nine (27%) of the control group and 55 (28%) of the intervention group were anaemic as defined by haemoglobin less than 110 g/l. There was no difference in the iron content of the diets offered to the two groups of children.

CONCLUSION

In this deprived population we have shown no reduction in anaemia using a targeted nutritional programme and have highlighted the difficulties in conducting health education programmes within the scope of current health resources.