Factors influencing iron nutrition among one-year-old healthy children in Sweden

Assessment of Dietary Iron Intake and Sources in Early Childhood in a Nationally Representative Cross-Sectional Survey

BACKGROUND

Iron deficiency has particular importance in early childhood because of its impact on growth and development. Preventive food-based strategies of iron deficiency require knowledge of intakes and sources of iron.

OBJECTIVE

This study aimed to assess daily iron intakes (DIIs) in 2013, to compare them with the dietary reference values, to assess their evolution since 1981, and to identify iron food sources among nonbreastfed French children younger than 3 years.

DESIGN

This was a nationwide cross-sectional survey conducted in 2013 in France to assess DIIs by means of comparing them with the dietary reference values. Parents' reported diet diaries were collected for 3 nonconsecutive days.

PARTICIPANTS/SETTING

Of the 1,184 children enrolled in the study, 1,035 nonbreastfed healthy children aged 0.5 to 35 months stratified into 11 age groups were included after informed consent was obtained from parents and according to a weighted quota sampling method.

MAIN OUTCOME MEASURES

DII from the different food sources and trends in their evolution from 1981 to 2013 was assessed.

STATISTICAL ANALYSES PERFORMED

Results are expressed as median with interquartile range and range and mean ± SD. Student t test was used with the 2-sided α level of significance set at 5%.

RESULTS

Mean ± SD DII was 6.7 ± 2.3 mg/d before 6 months, 8.2 ± 2.7 mg/d from 6 months to 1 year, and 7.0 ± 3.2 mg/d from 1 to 3 years. The prevalence of infants older than 7 months with a DII less than the dietary reference values was 52.5%, and that of young children was 30%. After slightly increasing until 2005, DIIs decreased thereafter. Formulas contributed to most of the DIIs up to 2 years of age. Cereals were the second largest contributor to DIIs, and meat accounted for a small part of iron intake.

CONCLUSIONS

A substantial number of children between 6 months and 3 years of age were at risk of insufficient iron intake. This risk increased from 2005 to 2013. The role of formula in ensuring iron intake is highlighted. More research on health outcomes of low iron intakes is needed.

Dietary Approaches to Iron Deficiency Prevention in Childhood—A Critical Public Health Issue

Iron is an essential nutrient, and individual iron status is determined by the regulation of iron absorption, which is driven by iron requirements. Iron deficiency (ID) disproportionately affects infants, children, and adolescents, particularly those who live in areas with unfavorable socioeconomic conditions. The main reason for this is that diet provides insufficient bioavailable iron to meet their needs. The consequences of ID include poor immune function and response to vaccination, and moderate ID anemia is associated with depressed neurodevelopment and impaired cognitive and academic performances. The persistently high prevalence of ID worldwide leads to the need for effective measures of ID prevention. The main strategies include the dietary diversification of foods with more bioavailable iron and/or the use of iron-fortified staple foods such as formula or cereals. However, this strategy may be limited due to its cost, especially in low-income countries where biofortification is a promising approach. Another option is iron supplementation. In terms of health policy, the choice between mass and targeted ID prevention depends on local conditions. In any case, this remains a critical public health issue in many countries that must be taken into consideration, especially in children under 5 years of age.

Iron status of young children in Europe

Iron deficiency (ID) is common in young children aged 6-36 mo. Although the hazards associated with iron deficiency anemia (IDA) are well known, concerns about risks associated with excess iron intake in young children are emerging. To characterize iron status in Europe, we describe the prevalence of ID, IDA, iron repletion, and excess stores with the use of published data from a systematic review on iron intake and deficiency rates, combined with other selected iron status data in young European children. Various definitions for ID and IDA were applied across studies. ID prevalence varied depending on socioeconomic status and type of milk fed (i.e., human or cow milk or formula). Without regard to these factors, ID was reported in 3-48% of children aged ≥12 mo across the countries. For 6- to 12-mo-old infants, based on studies that did not differentiate these factors, ID prevalence was 4-18%. IDA was <5% in most studies in Northern and Western Europe but was considerably higher in Eastern Europe (9-50%). According to current iron status data from a sample of healthy Western European children aged 12-36 mo, 69% were iron replete, and the 97.5th percentile for serum ferritin (SF) was 64.3 μg/L. In another sample, 79% of 24-mo-old children were iron replete, and the 97.5th percentile for SF was 57.3 μg/L. Average iron intake in most countries studied was close to or below the UK's Recommended Dietary Allowance. In conclusion, even in healthy European children aged 6-36 mo, ID is still common. In Western European populations for whom data were available, approximately three-quarters of children were found to be iron replete, and excess iron stores (SF >100 μg/L) did not appear to be a concern. Consensus on the definitions of iron repletion and excess stores, as well as on ID and IDA, is needed.

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.

Food and Nutrient Intake among 12-Month-Old Norwegian-Somali and Norwegian-Iraqi Infants

The aim of the present paper was to describe food and nutrient intake among 12-month-old Norwegian-Somali and Norwegian-Iraqi infants, with a focus on iron and vitamin D intake. A cross-sectional survey was conducted from August 2013 through September 2014. Eighty-nine mothers/infants of Somali origin and 77 mothers/infants of Iraqi origin residing in Eastern Norway participated in the study. Data were collected using two 24-h multiple-pass recalls. Forty percent of the Norwegian-Somali infants and 47% of the Norwegian-Iraqi infants were breastfed at 12 months of age (p = 0.414). Median energy percentages (E%) from protein, fat and carbohydrates were within the recommended intake ranges, except the level of saturated fats (12-13 E%). Median intakes of almost all micronutrients were above the recommended daily intakes. Most of the infants consumed iron-enriched products (81%) and received vitamin D supplements (84%). The median intakes of iron and vitamin D were significantly higher among infants receiving iron-enriched products and vitamin D supplements compared to infants not receiving such products (p < 0.001). The findings indicate that the food and nutrient intake of this group of infants in general seems to be in accordance with Norwegian dietary recommendations. Foods rich in iron and vitamin D supplements were important sources of the infants' intake of iron and vitamin D and should continue to be promoted.

Iron intakes of Australian infants and toddlers: findings from the Melbourne Infant Feeding, Activity and Nutrition Trial (InFANT) Program

Fe deficiency remains the most common nutritional deficiency worldwide and young children are at particular risk. Preventative food-based strategies require knowledge of current intakes, sources of Fe, and factors associated with low Fe intakes; yet few data are available for Australian children under 2 years. This study's objectives were to determine intakes and food sources of Fe for Australian infants and toddlers and identify non-dietary factors associated with Fe intake. Dietary, anthropometric and socio-demographic data from the Melbourne Infant Feeding, Activity and Nutrition Trial Program were analysed for 485 infants (mean age: 9·1 (sd 1·2) months) and 423 toddlers (mean age: 19·6 (sd 2·6) months) and their mothers. Dietary intakes were assessed via 24-h recalls over 3 non-consecutive days. Prevalence of inadequate Fe intake was estimated using the full probability approach. Associations between potential non-dietary predictors (sex, breast-feeding status, age when introduced to solid foods, maternal age, maternal education, maternal employment status and mother's country of birth) and Fe intakes were assessed using linear regression. Mean Fe intakes were 9·1 (sd 4·3) mg/d for infants and 6·6 (sd 2·4) mg/d for toddlers. Our results showed that 32·6 % of infants and 18·6 % of toddlers had inadequate Fe intake. Main food sources of Fe were Fe-fortified infant formula and cereals for infants and toddlers, respectively. Female sex and current breast-feeding were negatively associated with infant Fe intakes. Introduction to solid foods at or later than 6 months was negatively associated with Fe intake in toddlers. These data may facilitate food-based interventions to improve Australian children's Fe intake levels.

Iron Intake and Status of Children Aged 6-36 Months in Europe: A Systematic Review

Background: Iron deficiency is the most common nutritional disorder in the world. Young children are particularly vulnerable to the consequences of iron deficiency because of their rapidly developing brain. This review evaluates the prevalence of inadequate iron intake and iron deficiency (anaemia) in European children aged 6-36 months. Summary: Computerized searches for relevant articles were performed in November 2013. A total of 7,297 citations were screened and 44 studies conducted in 19 European countries were included in this review. In both infants (6-12 months) and young children (12-36 months), the mean value of iron intakes in most countries was close to the RDA. Nevertheless, proportions of inadequate intakes were considerable, ranging from about 10% in the Netherlands up to 50% in Austria, Finland and the United Kingdom. The prevalence of iron deficiency varied between studies and was influenced by children's characteristics. Two to 25% of infants aged 6-12 months were found to be iron deficient, with a higher prevalence in those who were socially vulnerable and those who were drinking cow's milk as a main type of drink in their first year of life. In children aged 12-36 months, prevalence rates of iron deficiency varied between 3 and 48%. Prevalence of iron deficiency anaemia in both age groups was high in Eastern Europe, as high as 50%, whereas the prevalence in Western Europe was generally below 5%. Key Messages: In most European countries, mean iron intakes of infants and children aged 6 to 36 months were found to be close to the RDA. Nevertheless, high proportions of inadequate intakes and high prevalence rates of iron deficiency were observed. Health programs should (keep) focus(ing) on iron malnutrition by educating parents on food choices for their children with iron-rich and iron-fortified foods, and encourage iron supplementation programmes where iron intakes are the lowest.

Prevalence and risk factors of iron deficiency in healthy young children in the southwestern Netherlands

OBJECTIVES

Iron deficiency (ID) and iron deficiency anemia (IDA), during the first years of life, are associated with delayed motor and neurological development. Many studies evaluated iron status without an assessment of an acute-phase protein to identify infection. Because most indicators of iron status are influenced by infection, these data may underestimate the ID prevalence. A food consumption survey in the Netherlands showed that the mean iron intake of children ages 2 to 3 years was below the advised adequate intake of 7 mg/day. The aim of the study was to investigate iron status in a well-defined, healthy population of young children in the southwestern region of the Netherlands and to identify risk factors for ID.

METHODS

We conducted a multicenter, observational study in healthy children ages 0.5 to 3 years. We defined ID as ferritin <12 μg/L and IDA when, in addition, hemoglobin was <110 g/L. Children with elevated C-reactive protein levels (>5 mg/L) or underlying causes for anemia were excluded. Parents filled in a questionnaire to identify risk factors for ID.

RESULTS

We included 400 children in the study. ID and IDA were detected in 18.8% and 8.5% of the children, respectively. The present use of formula and the visit of preschool/day care were associated with a lower prevalence of ID, and a high intake of cow's milk was associated with a higher prevalence of ID, after adjustment for age.

CONCLUSIONS

ID is present in 18.8% of healthy children ages 0.5 to 3 years and living in the southwestern region of the Netherlands. The present visit of preschool/day care and the use of formula are associated with a reduced risk of ID, whereas a high intake of cow's milk is associated with an increased risk of ID.