Iron Status In Infants Research Articles

Caregiving Arrangement and Nutrition: Good News with Some Reservations

The objective of this study was to assess the impact of caregiving arrangement on the iron and folate status of infants and toddlers reared at home or enrolled in centre-based, independent home, or licensed home care. One hundred and eighty-nine children aged 2 to 29 months were assessed 1 month prior to child care entry and at 6 months after entry into child care. Dietary (24-hour records), anthropometric (height, weight, head circumference) and biochemical (red blood cell folate, hematocrit, transferrin, and serum ferritin concentrations) methods were used to assess nutritional status. Frequency of illness was determined by a series of telephone interviews. Median intake of nutrients exceeded Canadian recommendations, regardless of care arrangement. Fifteen of 65 children had hematocrit values below age-specific cutoffs at the 6-month post-entry to child care visit. Children were frequently taken to obtain medical advice (average of 4 to 6 times during the study period) and 75% of subjects were prescribed at least one course of antibiotics. In conclusion, infants and toddlers in this study were generally well nourished, regardless of child care arrangement; however, iron status may remain an issue in this sample of infants and toddlers.

Plasma transferrin receptor levels and indices of erythropoiesis and iron status in healthy term infants.

The goal of this study was to determine if the postnatal changes in plasma transferrin receptor (TfR) levels in healthy infants were associated with changes in erythropoiesis or iron status. Longitudinal blood samples were obtained monthly from healthy term infants fed iron-fortified formula for the first 7 months and analyzed for plasma TfR and indices of erythropoiesis and iron status. Plasma TfR level rose during the first 2 months of life (p < 0.002). When examined for its association with indices of erythropoiesis, plasma TfR was negatively associated with hemoglobin (Hb) (p < 0.01), and positively associated with plasma erythropoietin (EPO) concentration (p < 0.005) and absolute reticulocyte count (p < 0.005). Plasma TfR was not associated with erythrocyte protoporphyrin. Although indices of iron status were not suggestive of iron deficiency, plasma TfR was negatively associated with plasma ferritin, Tf saturation, and plasma iron, and positively associated with total iron binding capacity (TIBC) (p < 0.0001 for all). Increases in plasma TfR levels were observed during normal infancy. The increases in plasma TfR levels correlate with increases in erythropoiesis without evidence for functional iron deficiency.

Effects of age of introduction of complementary foods on iron status of breast-fed infants in Honduras

To evaluate the effect of introducing complementary foods before 6 mo of age, we randomly assigned 164 infants who had been exclusively breast-fed for 4 mo to continue being exclusively breast-fed until 6 mo (EBF group) or to receive iron-fortified foods in addition to breast milk from 4 to 6 mo (BF+SF group). At 6 mo, the BF+SF group had higher mean iron intake (4 mg/d compared with 0.2 mg/d in EBF infants) and higher hemoglobin, hematocrit, and ferritin values than the EBF group (P < 0.05). The percentage with low hemoglobin (< 103 g/L) did not differ significantly between groups, but fewer infants in the BF+SF group had a low hematocrit (< 0.33; 21.4% compared with 32.0%, respectively; P < 0.05). The percentage of infants with ferritin concentrations < 12 microg/L at 6 mo was lower than the percentage with low hemoglobin or hematocrit, raising questions about the validity of the cutoffs at this age. Infants at greatest risk for anemia and low ferritin were those with birth weights < 2500 g; no infant with a birth weight > 3000 g had a low ferritin value at 6 mo. We conclude that the risk of iron deficiency is low among infants with birth weights > 3000 g who are exclusively breast-fed for 6 mo. Iron drops are recommended for low-birth-weight infants; for breast-fed infants with birth weights between 2500 and 3000 g, further research is needed to determine whether iron drops are more effective than complementary foods for preventing iron deficiency before 6 mo.

Cross-cultural patterns of growth and nutritional status of breast-fed infants

Growth patterns and iron status of infants who were breast-fed throughout their first year of life were examined in four populations: 1) a group of high socioeconomic status in California (the DARLING Study), 2) infants of normal birth weight (NBW) but from low-income families in Honduras, 3) low-birth-weight (LBW), full-term infants in Honduras, and 4) infants in Ghana. z Scores were calculated by using both the current National Center for Health Statistics reference data and a pooled data set based on breast-fed infants in six industrialized countries. The NBW infants in Honduras showed rapid growth in the first few months and were similar in weight-for-age to the DARLING infants until approximately 9 mo. By contrast, the LBW infants remained far below the other cohorts throughout the first 12 mo, despite an initial period of catch-up growth. In the Ghanaian infants, weight-for-age faltered beginning at 3-4 mo, but length-for-age did not falter until after 9 mo. Weight-for-length was highest in the NBW Honduran infants and lowest in the Ghanaian infants. When z scores were adjusted for birth weight and maternal height, no significant faltering was evident in either weight or length in any of the cohorts during the first 12 mo. Thus, when breast-feeding is continued during the first year of life and efforts are made to ensure adequate complementary feeding after 6 mo, if growth faltering occurs it is probably attributable to prenatal factors and maternal stature. Population differences in iron status reflected variation in birth weight and in the use of iron-rich foods. Therefore, efforts to prevent child stunting and malnutrition must pay attention to prenatal as well as postnatal factors.

Calcium and phosphorus supplementation of iron-fortified infant formula: no effect on iron status of healthy full-term infants

One objective of this clinical trial was to determine whether calcium and phosphorus supplementation of infant formula affects the iron status of healthy full-term infants. One hundred three infants were randomly assigned to receive iron-fortified, cow milk-based infant formula (465 mg Ca and 317 mg P/L) or the same formula with added calcium glycerophosphate (1800 mg Ca and 1390 mg P/L) for 9 mo. Reported calcium intake for supplemented infants was about four times that of control infants, ranging from a mean of 1741 mg/d at baseline to 1563 mg/d at 9 mo. There was no difference by treatment group in mean or median change from baseline of serum ferritin, total-iron-binding capacity, erythrocyte protoporphyrin, or hematocrit at 4 and 9 mo after enrollment. Incidence of iron deficiency was similar for both groups and no infant developed iron deficiency anemia during the trial. This study indicates that the well-documented inhibitory effect of calcium and phosphorus on iron absorption is not clinically important in infants fed iron-fortified infant formula.

Comparison of Two Iron Fortification Levels (8 &amp; 12 mg Fe) in Cows Milk-Based Formula: Effect on Growth and Hematology, Second Six Months of Life. † 567

Objective: To evaluate iron status in healthy iron sufficient infants fed an infant formula containing one of two iron fortification levels from six to twelve months of age.

Iron Status, Selected Nutrient Intakes, and Growth of Infants Being Treated for Phenylketonuria (PKU)

LEARNING OUTCOME: To describe iron status, nutrient intakes, and growth of infants with PKU undergoing therapy with Phenex(tm)-1 Ami no Acid Modified Medical Food with Iron.Several recent studies have reported deficient iron status and poor growth in children with PKU on therapy. Iron deficiency and malnutrition result in lower than normal IQ and should be prevented in infants with PKU who may become mentally retarded with elevated blood phenylalanine (PHE) concentrations. The purposes of this report are to describe nutrient intakes and growth of 27 infants, and iron status in 13 infants with classical PKU diagnosed at 10 ± 1 days (mean ± SEM) of age and treated for 6 months thereafter with Phenex-1. Three-day diet diaries were recorded monthly and nutrients were calculated by Amino Acid Analyzer© software. Iron status indices were analyzed at 6 months of study by standard techniques. Anthropometrics were measured at diagnosis and monthly by standard methods and compared to NCHS growth percentiles. Mean (± SEM) daily nutrient intakes during 6 months were: PHE 256 ± 17 mg, protein 17.2 ± 0.7 g, energy 659 ± 26 kcal, iron 11.6 ± 1.0 mg. Mean (± SEM) iron status indices at 6 months were: ferritin 38.5 ± 6.2 ng/mL, iron 47.0 ± 6.1 μg/dL, transferrin saturation 17.8 ± 2.5 %, total iron binding capacity 265 ± 14 μg/dL, hemoglobin 12.3 ± 0.1 g/dL, hematocrit 36.3 ± 0.1 % and mean corpuscular volume 79.0 ± 0.7 fl. Crown-heel length, head circumference, and weight percentiles at diagnosis were 46 ± 6, 54 ± 6, and 53 ± 5, respectively. At 6 months of age, crown-heel length, head circumference, and weight percentiles increased to 64 ± 5, 64 ± 5 and 74 ± 4, respectively. A mean iron intake almost twice the 1989 RDA for the birth to 0.5 year old infant supported normal mean indices of iron status. Excellent growth was achieved with a mean protein intake 132% and a mean energy intake of 101% of 1989 RDAs.

70 IRON DEFICIENCY ANEMIA IN INFANTS: WHO SHOULD WE SUPPLEMENT?

The authors evaluated the iron status of healthy infants at 9 months of age to determine the prevalence of iron deficiency anemia and to relate it with clinical, nutritional and socioeconomic factors. Of the first 300 infants born at São Macros Hospital in the last trimester of 1994 and invited for a consultation at 9 months of age, 220 attended and were evaluated for anthropometry, socioeconomic factors and nutrient intake using a questionnaire. Infant blood samples were also proposed to the parents for hemogram, serum iron, transferrin and serum ferritin. 27 parents refused. Five children with prematurity and intrauterine growth retardation were excluded. 188 infants were studied. Infants were labeled “anemic” if hemoglobin <11 g/dl, and with “iron deficiency anemia” (IDA) if, in addition, their ferritin was <12ng/ml [1]. Statistical analysis was made using chi-square and t tests and logistic regression. The mean (standard deviation) values for hemoglobin were 11,2g/dl (0,.9g/dl). The median (95% range) values for ferritin were 14,9g/ml (0,5-54,8ng/ml). 79 infants (43%) were considered to be anemic and 75 (41%) had a ferritin <12ng/ml. 37 (20%) met the criteria for IDA. Infants with IDA introduced solid food in average at 4,3 months compared with 3,9 months among those without IDA (p=0.03). Infants with IDA had had iron fortified formula for 2,3 months in average compared with 3,8 months among those without IDA (p<0.01). Finally, infants with IDA were breastfeeded for 4,8 months in average compared with 3,7 months among those without IDA (p=0.05). Age of introduction of cow's milk, vitamin C supplementation, social class, anthropometrics parameters were not significantly associated with IDA. In a stepwise logistic regression model which included all the above variables, only the number of months having iron fortified formula was significantly associated with IDA (OR=0.82, p=0.05). In conclusion, there was a high prevalence of iron deficiency anemia at 9 months of age and infants with prolonged breastfeeding and late diversification may iron supplementation.

Assessment of iron status in infants

Assessment of iron status in infants

Rethinking Current Recommendations to Introduce Solid Food between Four and Six Months to Exclusively Breastfeeding Infants

The World Health Organization and UNICEF currently recommend to start weaning between four and six months and no later than six months with the gradual introduction of solid food. However, some studies show that voluntary exclusive breastfeeding for about nine months is feasible and can sustain adequate weight gain and iron status in infants. It is therefore appropriate to review and evaluate the evidence presently used to set feeding policy. It appears that the alleged insufficiency of breast milk volume after four to six months is most likely due to management errors such as introducing supplements and spacing nursing bouts at wide intervals, both of which reduce milk yield. Women in developed countries who wish to breastfeed exclusively beyond four to six months should therefore not be discouraged from doing so. In developing countries, health authorities and non-governmental organisations should actively endorse exclusive breastfeeding for eight to nine months to protect infants against malnutrition and infections.

A longitudinal study of iron status in healthy Danish infants: effects of early iron status, growth velocity and dietary factors

In a cohort of term infants (n=91), followed from birth to 12 months, iron intake was examined by 24-h food records, and iron status by blood samples (haemoglobin (Hb)), mean corpuscular volume (MCV), serum values for iron, ferritin and transferrin, and erythrocyte protoporphyrin) at 2, 6 and 9 months. At 9 months of age, 5% had anaemia (Hb<105 g/l), but none had developed iron deficiency according to strict definitions used in this study (serum ferritin < 13 micrograms/l and transferrin saturation < 10%). Infants with high serum ferritin, serum transferrin and erythrocyte protoporphyrin values at one blood sampling also had high values at the following sample (tracking, r=0.45-0.80), suggesting that iron stores at delivery are an important determinant of iron stores during late infancy. Factors related to changes in serum ferritin were investigated by multiple linear regression. From 2 to 6 months, serum ferritin was negatively associated with knee-heel growth velocity (p=0.006) and positively with intake of infant formula (p=0.04). From 6 to 9 months it was negatively associated with intake of bread (p=0.001), and there was a trend for a positive association with intake of meat (p=0.07) and fish (p=0.08) and for a negative association with intake of cow's milk (p=0.07). In conclusion, those with a high growth velocity and a dietary pattern with a high intake of bread and a low intake of meat and fish had lower ferritin values and thereby an increased risk of depleting their iron stores later during infancy.

Iron status in breast-fed infants

Iron status of 30 infants who had been breast fed until their first birthday and who had never received cow milk, medicinal iron, or iron-enriched formula and cereals was investigated; 30% were anemic at 12 months of age. The duration of exclusive breast-feeding was significantly longer among nonanemic infants (6.5 vs 5.5 months). None of the infants who were exclusively breast fed for 7 months or more and 43% of those who were breast fed for a shorter time were anemic. Infants who were exclusively breast fed for a prolonged period had a good iron status at 12 and 24 months. (J P EDIATR 1995;127:429-31)

Iron status and intake of older infants fed formula vs cow milk with cereal

One hundred four infants were randomly assigned to receive whole cow milk plus iron-fortified cereal (WCM + C) in accord with the previous recommendations of the Committee of Nutrition/American Academy of Pediatrics (CON/AAP); one of two iron-fortified, follow-up formulas; or an iron-fortified infant formula. Mean iron intakes and vitamin C exceeded the recommended dietary allowance in all groups. By 12 mo of age, mean ferritin and mean corpuscular volume were lower in the WCM + C group and significantly more infants had serum ferritin concentrations < 12 micrograms/L. We conclude that infants 6-12 mo of age fed whole cow milk and iron-containing table food are at risk of developing depleted iron stores but not anemia. The iron insufficiency in these infants is not due to inadequate intake of iron or vitamin C, but probably to relatively poor bioavailability of iron in infant cereal.

Anaemia during pregnancy as a risk factor for infant iron deficiency: report from the Valencia Infant Anaemia Cohort (VIAC) study

A prospective cohort study with a 1-year follow-up of 156 neonates was carried out specifically designed to test the hypothesis that there is a positive relationship between iron deficiency during pregnancy and the development of the same disease in newborn infants. Exposure was defined as being born of a mother with ferropenic anaemia at delivery, and cases as the infants who developed iron deficiency during their first year of life. A statistically significant positive association was detected with an odds ratio of 6.57 (95% confidence limits 1.81-25.97). A stratified analysis was also performed to control the effect of potential confounders such as socio-economic variables, feeding practices and other factors linked with the iron status of infants. This second analytical procedure showed no alteration in the association detected in the simple analysis but that there was a statistically significant strong interaction between the quantity of cow's milk intake and the ferropenic status of the mother. These results show a relationship between iron deficiency of the mother at delivery and the development of iron deficiency in the infants. These new findings could be important in the development of new prevention programmes applied to pregnant women.

The Role of Bioanthropology in the Infant Formula Industry: Dietary Iron Status of American Infants

Bioanthropological methods and quantitative skills provided the tools needed to design and implement a large‐scale national survey of infant food consumption and dietary status. This article considers dietary iron intake of 847 American infants ranging in age from 6.5 months to 13.4 months. Iron intake was evaluated according to demographic characteristics and for different foods (cow's milk, iron‐fortified formula, non‐ironfortified formula, infant ceral, commercial baby food, and homeprepared table food) . Results indicated that, across all demographic characteristics considered, a large proportion of infants who were fed a diet that included either cow's milk or non‐iron‐fortified formula received amounts of iron below the RDA. In contrast, infants who were fed a diet that contained an ironfortified formula had median intakes of iron above the RDA. The results also underscore the importance of the WIC program (Special Supplemental Food Program for Women, Infants, and Children) in meeting the iron needs of high‐risk infants. The implications of low iron intake during infancy are considered in relation to aspects of growth and development.

Serum ferritin and iron status in mothers and newborn infants.

Iron status, including hemoglobin, S-ferritin, S-iron, S-transferrin, transferrin saturation and the erythrocyte zinc protoporphyrin/hemoglobin (ZPP:Hb) ratio, was evaluated in 85 healthy iron-supplemented mothers at parturition and in 74 of their term newborn infants. Of the mothers, 17% had a S-ferritin level less than 15 micrograms/l (i.e. depleted iron stores), 9.9% had S-ferritin less than 15 micrograms/l and transferrin saturation less than 15% (i.e. latent iron deficiency), and 2.4% had S-ferritin less than 15 micrograms/l, transferrin saturation less than 15% and Hb less than 120 g/l (i.e. iron deficiency anemia). Newborn infants had higher S-ferritin than mothers: median 128 micrograms/l versus 21 micrograms/l (p less than 0.0001), higher transferrin saturation: 48% vs. 21% (p less than 0.0001), and higher ZPP:Hb ratio: 74 mumol/mol Hb vs. 41 mumol/mol Hb (p less than 0.0001). During the first 5 post-natal days, median S-ferritin rose from 128 to 236 micrograms/l (p less than 0.0001). S-ferritin appeared to be the best single indicator of maternal iron status. Ferritin levels in newborn infants were correlated to levels in mothers (rs = 0.36, p less than 0.01), indicating that fetal iron reserves are dependent on maternal iron stores.

Nutritional iron status of infants fed according to current recommendations

We examined the iron nutritional status of healthy term infants in a longitudinal study from 15 through 365 days of age. All infants were fed according to the present austrian recommendations. Serum hemoglobin (Hb) decreased from 15 through 122 days of age and remained constant thereafter. At 365 days of age, only 4.7% of the infants had hemoglobin levels below 11 g/dl, which is considered the borderline value for anemia. Mean corpuscular volume (MCV) of erythrocytes was changing during infancy. Free erythrocyte protoporphyrin (FEP) was constant from 122 days through 365 days of age. The upper normal value of 3 micrograms/gHb for infants older than 122 days of age corresponded to that for children older than one year and adults. Serum ferritin (SF) decreased from 15 through 183 days of age and remained constant thereafter. At 365 days of age, only 9.3% of the infants had SF below 10 micrograms/l, which is considered the borderline concentration for depletion of iron stores. We found no differences of iron nutritional status between infants who were breastfed longer than 122 days and infants who were breastfed shorter than 122 days or were fed formula. Our findings indicate that the prevalence of iron deficiency anemia and depletion of the iron stores is lower than in previous studies. Changes in infant nutrition during the last years resulted in higher iron intake and lower prevalence of iron deficiency.

Impact of the WIC Program on the Iron Status of Infants

The WIC Program (Special Supplemental Food Program for Women, Infants and Children) was initiated in the early 1970s to improve the nutritional status of pregnant women, lactating women, and children from birth to 5 years of age who were at risk for nutritionally related health problems. Better hematologic status of a group of preschool-aged infants who were enrolled in the WIC Program from birth, as compared with another group of similar age and socioeconomic status from the pre-WIC Program era, suggests that participation in the WIC Program will help limit the development of iron depletion or iron deficiency anemia in young children, an important consideration in view of the deleterious hematologic and nonhematologic effects that have been attributed to those conditions.

The relationship between maternal and infant iron status.

Serum ferritin, iron and haemoglobin (Hb) concentrations were determined in 103 pregnant women and in the cord of their normal full-term offspring. In 50 of the cases the placental non-haem iron was also measured. The correlations between serum ferritin concentration and other measurements of iron status were similar in both maternal and cord blood suggesting that cord serum ferritin concentration may, as in adults, reflect neonatal iron stores. The inverse relationship found between cord serum ferritin and hb concentrations (r = -0.35, P less than 0.001) suggests that the amount of iron in foetal stores is influenced by that required for Hb. When Hb levels are elevated, as was demonstrated in babies of older mothers, significantly lower serum ferritin were found. Thus a low cord serum ferritin concentration does not necessarily indicate that less iron was transferred to the foetus. Maternal iron reserve, as reflected by serum ferritin concentration, was shown to be related to the amount of non-haem iron in the placenta (r = 0.41, P less than 0.005), but this iron does not seem to form part of foetal iron stores as it does not correlate with measurements of foetal iron status. A week correlation between cord and maternal serum ferritin concentrations was demonstrated (r = 0.21, P less than 0.05) but its biological significance is questionable.

846 EFFECT OF IRON DEFICIENCY WITHOUT ANEMIA ON INFANT BEHAVIOR

We have reported that treatment of infants with iron deficiency anemia produces a prompt increase in infant performance as measured by the Bayley scores of mental development (MDI). The present study was designed to determine if iron deficiency in the absence of anemia (Hb ≥11.0 g/dl) was also associated with behavioral alterations. Infants, 9-13 months of age, were classified based on hemoglobin, serum ferritin, erythrocyte protoporphyrin (FEP) and red cell size (MCV) as follows:Subjects were administered the Bayley MDI, treated with intramuscular iron, and then retested exactly one week later. All tests were administered by the same psychologist without knowledge of the infant's iron status. The mean increase in score in the test-retest for the 10 normals was 7.2; for those with iron depletion (8) it was 3.7 while the 15 infants with iron deficiency had a mean increase of 21 points (p <0.005). This study demonstrates that iron deficiency with biochemical (FEP) or cellular alterations (MCV) produces alterations in behavior that are independent of anemia and are rapidly reversible with iron therapy.