Need for iron supplementation in infants on prolonged breast feeding

Association of Human Milk Fortifier and Feeding Intolerance in Preterm Infants: A Cohort Study about Fortification Strategies in Southwest China

Background: The present strategy of administering human milk fortifier (HMF) in southwest China (swC) is mainly based on European and American populations’ guidelines. Additionally, some southwest Chinese preterm infants have been observed to develop feeding intolerance (FI) after administration of HMF. In order to develop adapted southwest Chinese guidelines for the administration of HMF to preterm infants and improve fortification strategies, a retrospective cohort study was performed to explore the association of the use of HMF and FI. Objective: To explore the association between HMF and FI in preterm infants and provide recommendations for its use in swC. Methods: This cohort study included 298 preterm infants from West China Second University Hospital. Maternal and infant clinical data were collected from electronic patient records. The infant cohort was divided into two groups based on the use/nonuse of HMF. The association between HMF and FI was evaluated using multivariate analysis. Nonlinear relationships and threshold effects were evaluated using generalized additive models and two-piecewise linear regression models. Results: The multivariate analysis confirmed that there is no significant association between HMF use and FI, but significant risk factors for FI include early HMF initiation (p = 0.02), full-strength HMF initiation (p = 0.04), and fast HMF supplementation rates (p = 0.004). Through smooth curve fitting and threshold effect analysis, we found that two inflection points, an initial concentration of HMF > 24 mg/mL and a HMF supplementation rate > 12.5 mg/mL/d, significantly increased FI risk. Conclusions: Routine HMF fortification can be safely used in preterm infants with gestational age < 32 wk or birth weight < 1500 g in swC, and we advise initiating fortification when enteral milk intake reaches 100 mL/kg/day, with an HMF concentration of 1:50 and if tolerated, increase to 1:25 more than 38 h. The recommended HMF supplementation rate differs from current guidelines and provides evidence for developing southwest Chinese guidelines. A prospective trial is needed in order to validate this proposal.

Nutrition for full-term and preterm infants

Providing adequate nutrition for the healthy full-term newborn is relatively easy; breast milk or formula is sufficient for the first six months of life. Although the full-term infant's organ systems are relatively mature, the gastrointestinal tract is often stressed by the demands of rapid growth, and feeding difficulties, such as gastroesophageal reflux, colic, milk allergy, and constipation, may occur that necessitate special handling. The small preterm infant, however, has many urgent nutritional needs; management is usually complicated by the fact that the infant's immature organs may be unable to cope with enteral feedings. Thus, total parenteral nutrition is necessary, with extensive laboratory monitoring of metabolic functions and precise attention to detail to avoid a prolonged period of partial starvation.

Breast-fed infants and their later cardiovascular health: a prospective study from birth to age 32 years

The aim of the present study was to evaluate the impact of infant breast-feeding on cardiovascular risk in young adults. This unique study group involved 158 subjects (eighty-two females) originally collected prospectively at birth in 1975 and followed up to the age of 32 years. Frequent visits during the first year guaranteed the knowledge of the precise duration of breast-feeding. All infants received at least some breast milk. Participants were assessed for both individual cardiovascular risk factors (blood pressure, plasma lipids, homeostatic model assessment of insulin resistance and waist circumference) and the general clinical risk of cardiovascular events by calculating the Framingham risk score (FRS) and the metabolic syndrome criteria score (NCEP-ATPIII; National Cholesterol Education Program's Adult Treatment Panel III). Data on lifestyle factors were carefully collected. Linear regression analyses revealed that the effect of the duration of breast-feeding was not relevant (0·02 decrease in the FRS per one additional breast-feeding month; 95 % CI - 0·19, 0·09). Similarly, the effect of breast-feeding was minor on all of the individual cardiovascular risk factors. We used sex, physical activity, dietary fat and vitamin C, smoking and alcohol consumption as covariates. Again, logistic regression analyses detected no significant impact of the duration of breast-feeding on the risk of the metabolic syndrome according to the NCEP-ATPIII (OR 0·95, 95 % CI 0·8, 1·1). The strongest independent predictor for later CVD risk was male sex. In conclusion, in this prospectively followed cohort of young adults born at term and at weight appropriate for gestational age, the duration of breast-feeding did not have an impact on the accumulation of cardiovascular risk factors.

Enteral iron supplementation in preterm and low birth weight infants

BACKGROUND

Preterm infants are at risk of exhausting their body iron stores much earlier than healthy term newborns. It is widespread practice to give enteral iron supplementation to preterm and low birth weight infants to prevent iron deficiency anaemia. However, it is unclear whether supplementing preterm and low birth weight infants with iron improves growth and neurodevelopment. It is suspected that excess exogenous iron can contribute to oxidative injury in preterm babies, causing or exacerbating conditions such as necrotising enterocolitis and retinopathy of prematurity. Additionally, the optimal dose and timing of commencement and cessation of iron supplementation are uncertain.

OBJECTIVES

To evaluate the effect of prophylactic enteral iron supplementation on growth and neurodevelopmental outcomes in preterm and low birth weight infants. The secondary objectives were to determine whether iron supplementation results in improved haematological parameters and prevents other causes of morbidity and mortality.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group. We searched Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 8), MEDLINE (1951 to August 2011), CINAHL (1982 to August 2011) and conference proceedings and previous reviews.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-randomised trials that compared enteral iron supplementation with no iron supplementation, or different regimens of enteral iron supplementation in preterm or low birth weight infants or both.

DATA COLLECTION AND ANALYSIS

We extracted data using the standard methods of the Cochrane Neonatal Review Group. Both review authors separately evaluated trial quality and data extraction. We synthesised data using risk ratios (RRs), risk differences (RDs) and weighted mean differences (WMDs). Where data about the methodology and results or both were lacking, we made an attempt to contact the study authors for further information.

MAIN RESULTS

We included twenty-six studies (2726 infants) in the analysis. The heterogeneity of participants, methods and results precluded an extensive quantitative synthesis. Of the 21 studies comparing iron supplementation with controls, none evaluated neurodevelopmental status as an outcome. Of thirteen studies reporting at least one growth parameter as an outcome, only one study of poor quality found a significant benefit of iron supplementation. Regarding haematological outcomes, no benefit for iron supplementation was demonstrated within the first 8.5 weeks of postnatal life (16 trials), except by two poor quality studies. After this age, most studies reported a higher mean haemoglobin in iron-supplemented infants. We were only able to include a limited number of studies in a quantitative meta-analysis, which suggested the haemoglobin concentration in iron-supplemented infants was higher by about 6 g/L at six to nine months. One study comparing high dose and low dose iron supplementation monitored neurodevelopmental outcome for one year, without finding any significant difference between the groups. One study comparing early versus late commencement of iron supplementation found no difference in cognitive outcome, but an increased rate of abnormal neurological examination in the late iron group at five years of age. The studies comparing high and low doses of iron indicated that there was no discernible haematological benefit in exceeding 'standard' doses of iron (i.e. 2 mg/kg/day to 3 mg/kg/day).

AUTHORS' CONCLUSIONS

The available data suggest that infants who receive iron supplementation have a slightly higher haemoglobin level, improved iron stores and a lower risk of developing iron deficiency anaemia when compared with those who are unsupplemented. However, it is unclear whether iron supplementation in preterm and low birth weight infants has long term benefits in terms of neurodevelopmental outcome and growth. The optimum timing and duration of iron supplementation remains unclear.

Home fortification with micronutrient sprinkles - A new approach for the prevention and treatment of nutritional anemias

Despite global goals set by United Nations' agencies over the past decade for significant reductions in iron deficiency anemia (IDA), it remains a largely unaddressed public health problem affecting more than two billion people, one-third of the world's population. The negative impact of IDA on health and human potential are greatest in the developing world, where it is estimated that 51% of children younger than four years of age are anemic, mainly due to a diet that is inadequate in bioavailable iron. Studies in both developed and developing countries have consistently shown mental and motor impairments that may not be reversible in children younger than two years of age with IDA. From a public health standpoint there are four possible interventions for the prevention of anemia: dietary diversification to include foods rich in absorbable iron; fortification of staple foods including targeted fortification of complementary foods for infants and young children; the provision of iron supplements; and 'home-fortification'. In response to a United Nations Children's Fund (UNICEF) request to develop a new approach to IDA, our research group developed 'Sprinkles' for home-fortification of complementary foods. Sprinkles are single-dose sachets (like small packets of sugar) containing micronutrients in powder form (encapsulated iron, zinc, vitamins A, C and D, and folic acid), which are easily sprinkled onto any home-prepared complementary food. Sprinkles were developed to overcome many of the side effects and disadvantages of iron drops. We have demonstrated that Sprinkles are as effective as iron drops in the treatment and prevention of anemia. Sprinkles are easier to use and are, therefore, better accepted than iron drops, which may improve adherence to iron interventions.

Infant milk feeding influences adult bone health: a prospective study from birth to 32 years

Background

Peak bone mass, attained by early adulthood, is influenced by genetic and life-style factors. Early infant feeding and duration of breastfeeding in particular, associate with several health-related parameters in childhood. The aim of this study was to examine whether the effects of early infant feeding extend to peak bone mass and other bone health characteristics at adult age.

Methods and Findings

A cohort of 158 adults (76 males) born in Helsinki, Finland, 1975, prospectively followed up from birth, underwent physical examination and bone densitometry to study bone area, bone mineral content (BMC), and bone mineral density (BMD) at 32 years of age. Life-style factors relevant for bone health were recorded. For data analysis the cohort was divided into three equal-size groups according to the total duration of breastfeeding (BF): Short (≤3 months), Intermediate and Prolonged (≥7 months) BF groups. In males short BF is associated with higher bone area, BMC, and BMD compared to longer BF. Males in the Short BF group had on average 4.7% higher whole body BMD than males in the Prolonged BF group. In multivariate analysis, after controlling for multiple confounding factors, the influence of BF duration on adult bone characteristics persisted in males. Differences between the three feeding groups were observed in lumbar spine bone area and BMC, and whole body BMD (MANCOVA; p = 0.025, p = 0.013, and p = 0.048, respectively), favoring the Short BF group. In women no differences were observed.

Conclusions

In men, early infant milk feeding may have a significant impact on adult bone health. A potential explanation is that the calcium and phosphate contents were strikingly higher in formula milk and commercial cow milk/cow milk dilutions as opposed to human milk. Our novel finding merits further studies to determine means to ensure optimal bone mass development in infants with prolonged breastfeeding.

Dry cereals fortified with electrolytic iron or ferrous fumarate are equally effective in breast-fed infants

Precooked, instant (dry) infant cereals in the US are fortified with electrolytic iron, a source of low reactivity and suspected low bioavailability. Iron from ferrous fumarate is presumed to be more available. In this study, we compared a dry infant rice cereal (Cereal L) fortified with electrolytic iron (54.5 mg iron/100 g cereal) to a similar cereal (Cereal M) fortified with ferrous fumarate (52.2 mg Fe/100 g) for efficacy in maintaining iron status and preventing iron deficiency (ID) in breast-fed infants. Ascorbic acid was included in both cereals. In this prospective, randomized double-blind trial, exclusively breast-fed infants were enrolled at 1 mo and iron status was determined periodically. At 4 mo, 3 infants had ID anemia and were excluded. Ninety-five infants were randomized at 4 mo, and 69 (36 Cereal L, 33 Cereal M) completed the intervention at 9 mo. From 4 to 9 mo, they consumed daily one of the study cereals. With each cereal, 2 infants had mild ID, a prevalence of 4.2%, but no infant developed ID anemia. There were no differences in iron status between study groups. Iron intake from the study cereals was (mean ± SD) 1.21 ± 0.31 mg⋅kg(-1)⋅d(-1) from Cereal L and 1.07 ± 0.40 mg⋅kg(-1)⋅d(-1) from Cereal M. Eleven infants had low birth iron endowment (plasma ferritin < 55 μg/L at 2 mo) and 54% of these infants had ID with or without anemia by 4 mo. We conclude that electrolytic iron and ferrous fumarate were equally efficacious as fortificants of this infant cereal.

Supplemental food may not prevent iron-deficiency anemia in infants

OBJECTIVE

The present study evaluates the role of supplementary food and medicinal iron intake in preventing iron deficiency anemia in children aged between 4 to 6 months.

METHODS

During a case-control study in "Tabriz Children Hospital", nutritional and medicinal-iron intake of 60 consecutively selected patients with iron-deficiency anemia were compared with 60 non-anemic children of similar age and sex distributions.

RESULTS

The mean hemoglobin concentration, corpuscular volume and serum iron were 9.11 g/dl, 65.41 fL and 19.33 microg/dl, in case group; and 12.6 g/dl, 75.18 fL and 78.28 microg/dl, in control group, respectively. There was no statistically significant difference between age of case and control groups when complementary-semisolid foods were started (P=0.058), but the mean of received medicinal iron in case group was significantly lower than control group (P<0.001).

CONCLUSION

Supplementary food intake alone is not efficient to prevent iron deficiency anemia since the age of 4-6 months. So, regular administration of medicinal iron is crucial to prevent iron-deficiency anemia in children aged 4-6 months.

Risk of infant anemia is associated with exclusive breast-feeding and maternal anemia in a Mexican cohort

The WHO recommends exclusive breast-feeding (EBF) for the first 6 mo of life to decrease the burden of infectious disease. However, some are concerned about the effect of EBF >6 mo on iron status of children in developing countries in which anemia is prevalent. This study examines the risk of anemia in relation to the duration of EBF and maternal anemia in a birth cohort studied between March 1998 and April 2003. All infant birth weights were >or=2.2 kg. All mothers received home-based peer counseling to promote EBF. Infant feeding data were collected weekly. Nurses measured hemoglobin (Hb) values every 3 mo. Hb was measured in 183 infants at 9 mo of age. Anemia at 9 mo was defined as a Hb value <100 g/L. EBF was defined by WHO criteria and ranged in duration from 0 to 31 wk. At 9 mo, Hb (mean +/- SEM) was 114 +/- 0.9 g/L; 23 children (12.5%) had Hb levels <100 g/L. EBF >6 mo, but not EBF 4-6 mo, was associated with increased risk of infant anemia compared with EBF <4 mo (odds ratio=18.4, 95% CI=1.9, 174.0). Maternal anemia was independently (P=0.03) associated with a 3-fold increased risk of infant anemia. These associations were not explained by confounding with other maternal or infant factors. By linear regression, a lower infant Hb at 9 mo was associated with increased EBF duration among mothers who had a history of anemia (beta=-0.07, P=0.003), but not among mothers with no history of anemia. Infants who are exclusively breast-fed for >6 mo in developing countries may be at increased risk of anemia, especially among mothers with a poor iron status; greater attention to this issue is warranted.

Breastfeeding is protective against dental fluorosis in a nonfluoridated rural area of Ontario, Canada

To determine the relationship between early infant feeding and dental fluorosis in a non-fluoridated area, 1367 children were examined for fluorosis and given a water sample vial and questionnaire. 752 families responded (55%). Breastfeeding was reported by 69% of respondents, with 53.6% breastfed < 6 months, 35.3% 6-12 months, and 11.1% > 1 year. Formula feeding was reported by 84% of respondents, with 60.3% and 39.7% formula fed for < 1 year and > 1 year, respectively. Fluorosis prevalence was 23.3% and was present in 27.2%, 19.6% and 13.8% of children breastfed for < 6 months, 6-12 months, and > 12 months, respectively (P < .05). About 87% of formula fed children had tap water added to the bottle. Breastfeeding for > 6 months may protect children from developing fluorosis in the permanent incisors. This study suggests that dental professionals should support efforts to increase the rate and duration of breastfeeding.

Meat intake and iron status in late infancy: an intervention study

BACKGROUND

Highly bioavailable dietary iron is needed to ensure optimal iron status in infants during weaning. The purpose of the current study was to examine the effect of increased meat intake on hemoglobin concentration (Hb), serum ferritin (SF), and serum transferrin receptors (TfR) in late infancy.

METHODS

Forty-one healthy, term, partially breast-fed 8-month-old infants were randomized into two groups: a low-meat group (LMG), in which infants received a diet with a mean meat content of 10 g/day and a high-meat group (HMG), in which infants received a diet with a mean meat content of 27 g/day. The intervention lasted for 2 months, and blood samples were drawn on the first and the last days of the intervention.

RESULTS

At the beginning of the intervention, no significant differences were found in Hb, SF, TfR values between the two groups. After the intervention, there was a significant (p = 0.008) difference in the change in hemoglobin (delta Hb) concentration. In the LMG delta Hb was -4.9 g/l (range, -12.9-5.6 g/l) and in the HMG -0.6 g/l (range, -12.1-7.3 g/l). There was no significant difference in change in SF or TfR concentrations between the LMG and the HMG. The intake of iron from meat (mean; range) was significantly higher (p = 0.0001) in the HMG (0.4 mg/day; 0.02-0.7 mg/day) than in the LMG (0.1 mg/day; 0.03-0.5 mg/day). However, there was no significant difference in total iron intake between the HMG (3.1 mg/day; 0.4-6.2 mg/day) and the LMG (3.4 mg/day; 1.4-6.1 mg/day).

CONCLUSION

The results suggest that an increase in meat intake can prevent a decrease in Hb in late infancy, probably by enhancing iron absorption. However, there was no effect on iron stores or on cellular iron deficiency, evaluated by SF and TfR levels, respectively.

Breastfeeding and the use of human milk. American Academy of Pediatrics. Work Group on Breastfeeding

This policy statement on breastfeeding replaces the previous policy statement of the American Academy of Pediatrics, reflecting the considerable advances that have occurred in recent years in the scientific knowledge of the benefits of breastfeeding, in the mechanisms underlying these benefits, and in the practice of breastfeeding. This document summarizes the benefits of breastfeeding to the infant, the mother, and the nation, and sets forth principles to guide the pediatrician and other health care providers in the initiation and maintenance of breastfeeding. The policy statement also delineates the various ways in which pediatricians can promote, protect, and support breastfeeding, not only in their individual practices but also in the hospital, medical school, community, and nation.

Correction of iron deficiency with an iron-fortified fluid whole cow's milk in children: results of a pilot study

PURPOSE

This study assesses the efficacy of an iron-fortified (15 mg Fe, as stabilized ferrous sulfate (SFE-171), per liter) fluid whole cow's milk (IFFWCM) for the treatment of mild iron deficiency in children. Previous studies in healthy adult volunteers showed a mean 10.2 +/- 4.7% iron absorption.

PATIENTS AND METHODS

Seventeen children (12 to 48 months old) with iron deficiency (serum iron (SI) < 60 micrograms/dl, transferrin saturation (TS) < 15%, serum ferritin (SF) < 15 ng/ml) were included in this study; 11 of them were anemic. As treatment, they received IFFWCM, instead of the customary whole cow's milk, for at least 4 months; medicinal iron was not administered. Hematocrit (Hct), hemoglobin (Hb), SI, TS, and SF were determined monthly.

RESULTS

The Hb increased from 10.3 +/- 0.8 to 12.7 +/- 0.6 g/dl in the group with anemia (delta F-B: 2.4 +/- 1.0 g/dl) and from 12.6 +/- 0.7 to 13.5 +/- 0.3 g/dl in the group without anemia (delta F-B: 0.9 +/- 0.5 g/dl); the difference between both groups was significant (p < 0.01); the rate for Hct values showed a similar pattern. In the whole group, the SI increased to 84.8 +/- 37.4 micrograms/dl, with no difference between children with anemia and children without anemia; TS showed a similar pattern (delta F-B: 19.0 +/- 11.0%). The mean SF increased from 12.1 +/- 2.7 ng/ml to 27.9 +/- 25.4 ng/ml. Normal values for Hct, Hb, SI, and TS were reached by 100% of children; the rate for SF was 56.3%. Time required to reach normal Hct in the children with anemia was 59.4 +/- 33.0 days. Acceptance and tolerance were excellent; no treatment had to be discontinued. The group of patients with anemia was compared with an historical group composed of 55 children matched for age, basal Hct, and achieved Hct increase, treated with medicinal FS (4-6 mg/kg/day): time required to reach normal Hct was shorter in the FS-treated group (39.0 +/- 14.5 days) (p = 0.050).

CONCLUSION

The use of IFFWCM alone could be an effective, relatively inexpensive, and well-tolerated treatment of iron deficiency in children.

Strategies for the prevention of iron deficiency: iron in infant formulas and baby foods

Iron deficiency is the most prevalent nutrition deficiency among infants and young children in industrialized as well as developing countries. It is a condition that is preventable through appropriate dietary measures. The infant born at term is endowed with a sizable amount of iron, which allows the infant to be fed a nearly iron-free diet (e.g., breast milk) for 4-6 months without becoming overtly iron deficient. This has led some to conclude that depletion of iron stores in healthy infants is a normal and, hence, innocuous process that usually gives way to gradual repletion of iron stores as dietary diversification leads to greater iron intakes. Preservation of maternal iron stores at the expense of infant iron stores may have offered survival advantages to the human species during evolution. But there is no evidence that depletion of iron stores can offer advantages to infants in industrialized or developing countries. On the contrary, there is ample documentation of shortterm as well as long-term adverse effects from iron deficiency. Prudence therefore dictates that a high priority be assigned to the prevention of iron depletion and deficiency among infants and young children worldwide.

Reduced haemoglobin levels in infants presenting with apparent life-threatening events--a retrospective investigation

Anaemia has been shown to be associated with an increased apnoeic pause frequency and with cyanotic breath-holding spells. In this study, the relationship between anaemia and apparent life-threatening events was retrospectively investigated in 72 term infants referred for assessment and home monitoring following an apparent life-threatening event. For 41 infants (25 male, 16 female; 38 Caucasian, three Asian) a venous red blood cell count was available. Their median age at the time of the apparent life-threatening event was 2.0 (0.6-6.7) months. The Hb levels in these 41 infants were plotted against normal data from the literature. Thirty-four infants had Hb levels below the mean, whilst six infants had values above the corresponding normal mean; the one remaining infant had a Hb value identical to the normal mean. Significantly more infants than expected had Hb levels below the mean (p less than 0.001, binomial test). Anaemia may have played a role in the pathophysiology leading to life-threatening events in some of the infants investigated in this study.

Relation of infant feeding to adult serum cholesterol concentration and death from ischaemic heart disease

OBJECTIVE

To examine whether method of infant feeding is associated with adult serum lipid concentrations and mortality from ischaemic heart disease.

DESIGN

Follow up study of men born during 1911-30.

SETTING

Hertfordshire, England.

SUBJECTS

5718 men, for 5471 of whom information on infant feeding had been recorded by health visitors and 1314 of whom had died. 485 of the men born during 1920-30 and still living in Hertfordshire who had blood lipid measurements.

MAIN OUTCOME MEASURES

Death from ischaemic heart disease; serum cholesterol and apolipoprotein concentrations.

RESULTS

474 men had died from ischaemic heart disease. Standardised mortality ratios were 97 (95% confidence interval 81 to 115) in men who had been breast fed and had not been weaned at 1 year, 79 (69 to 90) in breast fed men who had been weaned at 1 year, and 73 (59 to 89) in men who had been breast and bottle fed. Compared with men weaned before one year men not weaned had higher mean serum concentrations of total cholesterol (6.9 (not weaned) v 6.6 (weaned) mmol/l), low density lipoprotein cholesterol (5.0 v 4.6 mmol/l) and apolipoprotein B (1.14 v 1.08 g/l). Men who had been bottle fed also had a high standardised mortality ratio for ischaemic heart disease (95; 68 to 130) and high mean serum concentrations of total cholesterol (7.0 mmol/l), low density lipoprotein cholesterol (5.1 mmol/l), and apolipoprotein B (1.14 g/l). In all feeding groups serum apolipoprotein B concentrations were lower in men with higher birth weight and weight at 1 year.

CONCLUSIONS

Age of weaning and method of infant feeding may influence adult serum low density lipoprotein cholesterol concentrations and mortality from ischaemic heart disease. Adult serum apolipoprotein B concentrations are related to growth in fetal life and infancy.

Minerals and trace elements in milk

The nutritional roles, requirements, and metabolism and the quantitative relationship between dietary intakes and health for a number of the minerals and trace elements have been more clearly defined in recent years, but there are still considerable deficiencies in our understanding of these issues, e.g., the significance of calcium in the etiology and treatment of osteoporosis and hypertension. Reliable information is now available on the content, and the principal factors affecting it, of most of the minerals and trace elements in human and cow's milks. However, for some of the trace elements, there is still a wide variation in reported values in the literature, which is due, at least in part, to analytical difficulties. The contribution of cow milk and milk products to the diet in Western countries is significant for sodium, potassium, chloride, calcium, phosphorus, zinc, and iodine. Iodine is the only trace element for which there has been any suggestion of excessive amounts in cow milk. However, there is evidence of a decline in milk iodine concentrations in the United States in recent years, although the situation in other countries less clear. Breast milk usually has adequate mineral and trace element contents for feeding full-term infants, with the exceptions of fluoride, for which supplementation of infants is recommended, and of selenium in some countries, such as Finland and New Zealand, where maternal intakes are low. However, breast milk selenium contents have increased in these countries in recent years due to increased maternal selenium intakes. The concentrations of minerals and trace elements in infant formulas for full-term infants are generally higher than in human milk, and all appear to be more than adequate, with the possible exception of selenium, which may need to be increased in some formulas. Considerable changes in the mineral and trace element contents of formulas have been instituted in recent years in the light of improved knowledge of infant requirements. While the chemical forms of the macrominerals and some of the trace elements (iron, zinc, copper, and manganese) in milks are fairly well defined, the forms of many of the trace elements are unknown. Sodium, potassium, chloride, and iodine are believed to be almost totally absorbed from milks and infant formulas.(ABSTRACT TRUNCATED AT 400 WORDS)

Iron status with different infant feeding regimens: relevance to screening and prevention of iron deficiency

The objective of this study was to evaluate the benefit of screening for anemia in infants in relation to their previous diet. The iron status of 854 nine-month-old infants on three different feeding regimens and on a regimen including iron dextran injection was determined by analysis of hemoglobin, serum ferritin, and erythrocyte protoporphyrin levels and of serum transferrin saturation. Infants were categorized as having iron deficiency if two or three of the three biochemical test results were abnormal and as having iron deficiency anemia if, in addition, the hemoglobin level was less than 110 gm/L. The prevalence of iron deficiency was highest in infants fed cow milk formula without added iron (37.5%), intermediate in the group fed human milk (26.5%), much lower in those fed cow milk formula with added iron (8.0%), and virtually absent in those injected with iron dextran (1.3%). The corresponding values for iron deficiency anemia were 20.2%, 14.7%, 0.6%, and 0%, respectively. The use of iron supplements is therefore justified in infants fed cow milk formula without added iron, even when there is no biochemical evidence of iron deficiency. The low prevalence of iron deficiency in the group fed iron-fortified formula appears to make it unnecessary to screen routinely for anemia in such infants. These results also support the recommendation that infants who are exclusively fed human milk for 9 months need an additional source of iron after about 6 months of age.

Iron availability from an infant formula supplemented with bovine lactoferrin

Iron balance studies were performed in 16 term infants from their 3rd until their 17th week of life. The balance studies were performed at home and comprised five periods with an interval of 3 to 4 weeks, each consisting of three 24-hour collections of milk and stool samples. Seven infants were fed an adapted infant formula supplemented with bovine lactoferrin (100 mg/100 ml) and nine received the same formula without lactoferrin. The lactoferrin supplemented group received 169 micrograms iron/kg b.w. x day and retained 63 micrograms/kg b.w. x day. The mean iron intake of infants fed with the adapted formula without supplementation of lactoferrin was 118 micrograms/kg b.w. x day. The retention of iron was 43 micrograms/kg b.w. x day. Mean percentage retention of iron in the supplemented group was 36%, in the non-supplemented group 28%.

Surveillance for anaemia: risk factors in patterns of milk intake

The association between patterns of milk intake and anaemia was studied during a surveillance programme for iron deficiency anaemia. Children aged 8-24 months were examined when they attended a routine immunisation clinic. Haemoglobin was measured on finger prick blood samples using a portable haemoglobinometer, and a dietary questionnaire was completed, with special emphasis on the type and volume of milk intake and the age at which whole cows' milk was introduced. Anaemia (defined as a haemoglobin concentration of less than 110 g/l) was diagnosed in 33 children (22%) and was more common among children who were not white. Continued feeding with breast milk and the early introduction of whole cows' milk were associated with a significantly higher prevalence of anaemia. No child taking formula milk was anaemic. Asian children drank significantly more milk a day than other groups, but there was no correlation between daily milk intake and haemoglobin concentration.

Iron for the suckling

Knowledge of the metabolism of iron by young infants is incomplete but combining practical studies based on detecting the onset of iron depletion with isotopic studies of iron economy may improve our understanding of iron metabolism in infants and our strategies for ensuring their iron supply. The iron accumulated by the fetus is enough to delay the risk of iron deficiency until four, and two months of age in term and preterm infants respectively. Breast fed term infants may not need extra iron until they are six months or older; but whereas low iron formulas are adequate for other infants until about four months of age, thereafter infants need extra iron which can be provided effectively in iron fortified formulas. Breast fed low birth weight infants need iron supplements from two months of age but those fed specific low birth weight formulas which are iron fortified should not need extra iron.

Prevention of iron deficiency by milk fortification. The Chilean experience

A large proportion of the milk consumed by infants in Chile is distributed by a National Food Supplementary Program. Efforts to prevent iron deficiency by milk fortification started several years ago. Initially a field study involving the simple addition of ferrous sulfate to a low-fat powdered milk was only partially successful due to the relatively low iron absorption from this product. Following the observation that the enrichment of milk with ascorbic acid markedly improved iron bioavailability, a new fortified formula was developed and has been tested in the field since 1976. This is powdered full-fat milk, biologically acidified and fortified with 15 mg Fe, as ferrous sulfate, and 100 mg ascorbic acid per 100 g powder. In a pilot study, 276 infants spontaneously weaned before 3 months of age received the fortified milk, and 278 infants receiving unfortified milk served as controls. At the end of the study (15 months of age) anemia (Hb less than 11 g/dl) was present in 25.7% of unfortified infants compared with only 2.5% in those fortified. Saturation of Transferrin less than 9% was present in 33.8% and serum ferritin less than 10 micrograms/l in 39.1% of the nonfortified infants. The figures for the fortified group were 7% and 8.5% respectively. Acceptance of the fortified formula was good. Following these observations, and as a previous step to the use of the fortified milk in the national program, the formula was tested in 7 National Health Service inner city community clinics under regular milk distribution.(ABSTRACT TRUNCATED AT 250 WORDS)

Iron deficiency in children. Update on an old problem

Over the past 25 years the incidence of iron deficiency anemia has decreased remarkably. This decline has resulted directly from a program of prevention that is based on a detailed understanding of iron lack in infants and children. However, iron deficiency without anemia--subtle iron deficiency--remains a problem. The negative impact of iron deficiency on brain function has recently been demonstrated in animal as well as human studies. The behavioral effects noted in infants and toddlers can be seen with subtle iron deficiency as well as with anemia. Although behavioral abnormalities in the very young appear to be correctable by iron treatment, prolonged iron deficiency may lead to irreversible effects on brain function. These recent findings should further encourage continued vigilance in preventing the old problem of iron deficiency.

Iron balances in infant nutrition

Iron balance studies were performed in 17 full term male infants from their 3rd until their 17th week of life. The balance studies were made in the infant's home and comprised 5 periods with an interval of 3-4 weeks, each consisting of three 24-hour collections. Ten infants were breast-fed, 3 received an adapted infant formula (P1, iron content 1.1 mg/l) and 4 were given the same formula enriched with iron, copper and zinc (P2, iron content 10.35 mg/l). From the 3rd to the 17th week of life the breast-fed infants got a mean iron intake of 0.2 mg/kg body weight X 3 days and they retained 0.09 mg/kg b.w. X 3 days. The P1 group received 0.48 and 0.47 mg/kg b.w. X 3 days and retained -0.01 and -0.5 mg iron/kg b.w. X 3 days, while the P2 group had an intake from 5.04 to 6.38 mg b.w. X 3 days and retained between 1.13 and 3.66 mg iron/kg b.w. X 3 days. Comparing the 3 groups it can be concluded that the P1 group retained definitely less iron than the breast-fed group, whereas the P2 group retained 12 to 40 times more iron than the breast-fed babies.

Iron status in low birth weight infants on breast and formula feeding

Iron status in 15 low birth weight infants, 1000-2499 g, on breast feeding was studied longitudinally for the first 6 months of age, and the findings compared to those of 30 low birth weight infants receiving a proprietary iron-fortified formula. The two groups received no iron supplement until they developed iron deficiency. The incidence of iron deficiency at 6 months was significantly greater in the breast-fed group than in the formula-fed group (86% v 33%). The breast-fed group had significantly lower serum ferritin and hemoglobin values after 4 months of age. The findings indicate that breast-fed low birth weight infants have a higher risk of developing iron deficiency and should receive iron supplementation from 2 months of age.

Controversies in neonatal nutrition

The assessment of growth parameters remains one of the most practical and valuable tools to estimate nutritional status in neonates. Growth assessment in full-term infants is performed by using charts developed by the National Center for Health and Statistics. The assessment of post-natal growth in premature infants is controversial and can be performed by using either intrauterine or extrauterine standards. The selection of appropriate growth charts should be based on clinical, demographic, ethnic, and socioeconomic similarities of the population used for reference. Daily energy intakes ranging from 100 to 120 kcal/kg/day have been recommended for full-term infants, while higher intakes ranging from 114 to 181 kcal/kg/day have been recommended for premature neonates. Full-term infants should be nursed or nipple fed on demand; however, premature infants should ideally be tube fed by intermittent gastric feeding (gavage). Continuous gastric and transpyloric feedings are indicated in selected infants. Human milk is a preferred food for full-term infants during the first six months of life; however, this precept does not suggest that all infants who are exclusively breast-fed will grow adequately. Preterm human milk is also a preferred food for the low birthweight infant, provided nutritional supplements are used. It is unclear whether the supplementation of vitamin D, iron, and fluoride in full-term breast-fed infants should be started at birth, at the time of initiation of solid foods, or at the age of six months. The routine supplementation of multivitamins, folic acid, and vitamin E to all low birthweight infants is controversial. Most investigators suggest vitamin supplementation be given until the intake of formula or breast milk is sufficient to meet daily requirements. Vitamin E appears to exert a protective effect in premature infants against the development of severe retinopathy. The supplementation of vitamin E should be dependent upon the serum vitamin E concentration. It is controversial whether iron supplementation for premature infants should be initiated soon after birth or at two months of age, or whether higher doses of iron should be given to very low birthweight infants. If iron supplementation is started at birth, vitamin E status should be closely monitored. Although the optimal intakes of calcium and phosphorus in infant feedings have not been firmly established, the levels of calcium and phosphorus in human milk appear to be inadequate for the growing low birthweight infant.(ABSTRACT TRUNCATED AT 400 WORDS)

Nutrient intakes of older infants: effect of different milk feedings

Using 24-hour dietary and nutrient intake of 293 infants 7-12 months of age from NHANES II, 1976-80, we determined the hypothetical effects of different milk feedings on total intake of 12 nutrients. Infants were grouped by age at 7-8, 9-10, and 11-12 months. Human milk (HM), Fe-fortified infant formula (I-FM), whole cow's milk (WCM), and 2% lowfat milk (2%) were substituted to provide the same energy as that calculated from the difference between median energy intake provided by solid foods and the total diet. Nutrients from milk feedings were added to median nutrient intake from solid foods. Use of WCM or 2% resulted in low total intakes of Fe (6.3-11.1 mg) and linoleic acid (0.5-2.5 g) and high intakes of protein (32-47 g), Na (630-1,200 mg), K (1,400-1,900 mg), and Ca (920-1,170 mg) relative to the RDA. Feeding of HM provided total intakes that met the RDA for each nutrient except Fe (6.1-10.8 mg) and Ca (350-370 mg). When I-FM was fed, the RDA was met for each nutrient except Ca (370-490 mg) at all ages and Fe (13.1 mg) at 11-12 months. Estimated safe and adequate daily intake of Na was exceeded at 9-10 months by infants fed WCM/2% and at 11-12 months by all infants regardless of milk feeding, primarily because of the high Na content of solid foods. These data confirm that the milk feeding is still the major determinant of total nutrient intake in the second 6 months of life.

Iron deficiency in the weanling: a nutritional problem on the way to resolution

The rapidly growing weanling becomes vulnerable to iron deficiency when neonatal iron stores have been consumed after the first few months following birth. Whether the infant will progress from the harmless condition of depleted iron stores to the physiological handicaps associated with iron deficiency depends on the selection of foods during the period of weaning. Consumption of fresh cow's milk and of unfortified cow's milk formulas and cereal products predispose to iron deficiency. Breast feeding, iron- and ascorbic acid-fortified cow's milk formulas and cereals, and the use of ascorbic acid-rich foods and meat decrease the likelihood of iron deficiency. Recent changes in infant feeding practices in the United States have been associated with a marked decline in iron deficiency anemia. A challenge for the future will be to extend this success, particularly to developing countries.

Successful breast feeding: the mother's dilemma

A content analysis of 141 articles on breast feeding by discipline revealed differences in the factors considered necessary for breast feeding success and in the criteria used to determine success. Whereas medical articles focused on maternal factors prenatally and infant health post-natally, or the length of time breast feeding was maintained, lay articles focused on the relationship of the mother with her infant (the nursing couple) and the mother's ability to manage breast feeding within the family context. The implications of this discrepancy for nursing practice and research are discussed.

Exclusive breast-feeding for 9 months: risk of iron deficiency

Thirty-six infants who were exclusively breast-fed were observed for 9 months. Thirty-two infants who were completely weaned prior to age 3 1/2 months served as controls; these infants received iron supplementation in formula and solid foods. A great majority of exclusively breast-fed infants were able to maintain their iron status at the same level as that of the control infants. The mean concentration of hemoglobin was higher in breast-fed infants than in control infants at ages 4 and 6 months. However, six breast-fed infants required iron medication because they had laboratory evidence of iron deficiency, although none had anemia. Maternal iron supplementation during breast-feeding, even in large daily doses, did not have any effect on the infants' iron nutrition, nor prevent infants from developing some signs of iron deficiency. Our data indicate that it is safe in exclusively breast-fed infants to shift the starting age for introduction of iron to 6 months.

Iron sufficiency with prolonged exclusive breast-feeding in Peruvian infants

Serum ferritin and erythrocyte porphyrin concentrations were measured in seven Peruvian infants, who ranged in age from 7.5-12.0 months (mean: 9.3 months), who had been exclusively breast-fed all their lives. No infant had evidence of iron deficiency as reflected by a reduced serum ferritin, or an increased erythrocyte porphyrin. Mean serum ferritin and erythrocyte porphyrin values in these seven infants were similar to those of 40 nonanemic, noniron-deficient U.S. infants who ranged in age from 9 to 12 months, on a mixed diet. These findings illustrate that exclusively breast-feeding an infant for at least 9 months of life meets the iron requirements of the full-term infant.

Iron deficiency in one-year-old infants: comparison of results of a therapeutic trial in infants with anemia or low-normal hemoglobin values

The purpose of this study was to determine the Hgb response to a therapeutic trial of iron in infants with anemia compared to those with low-normal hemoglobin values. Hgb was determined in 1.128 one-year-old infants. The 278 infants (25%) who had an Hgb less than 11.5 gm/dl were given a three-month oral course of ferrous sulfate (3 mg iron/kg/day); the regimen was satisfactorily completed by 188 infants. Of the 75 infants whose initial capillary Hgb was in the anemic range (Hgb less than 11.0 gm/dl), 45% had an increase in venous Hgb greater than or equal to 1.0 gm/dl. Of the 113 infants with initial capillary values in the low-normal range (11.0 to 11.4 gm/dl), 28% had greater than or equal to 1.0 gm/dl Hgb response. Despite the lower rate of response in the low-normal group, almost half of the infants with a greater than or equal to 1 gm/dl response would have been missed by using the generally accepted cutoff value of 11 gm/dl for a therapeutic trial. Because of the low cost and simplicity of a therapeutic trial, we favor including the low-normal Hgb group for a therapeutic trial of iron in order to avoid missing iron-responsive individuals among groups of infants with a similarly high prevalence of iron deficiency anemia.

Iron in human milk

The distribution of iron among various fractions of human milk was determined by gel filtration, ultrafiltration, and atomic absorption spectrophotometry. Total iron varied between 0.26 and 0.73 microgram/ml; 1.5 to 46% of the iron was bound to the lipid fraction and 18 to 56% was found in a low molecular weight fraction. Only a small amount of iron was bound to lactoferrin, the major iron-binding protein of human milk; the iron saturation of this protein was found to be 1 to 4%, at the most. Thus, much less iron is bound to lactoferrin than earlier reported; this may be important in regard to the suggested role of this protein as a bacteriostatic agent. A correlation was found between iron and fat content during the course of a single nursing, but not between iron and lactoferrin.