Premature complementary feeding is associated with poorer growth of vietnamese children

The objective of this longitudinal study was to investigate the association between the premature initiation of complementary feeding and physical growth of children. Four cohorts of newborn children were included, consisting of 90 infants born in 1981, 90 in 1982, 60 infants in 1983 and 60 in 1984. The weights and heights of children were measured monthly up to 1 y, then every 3 mo for y 2 and 3, and once every 6 mo in y 4. Information on feeding practices and diseases of the children was obtained by interviewing the mothers at each home visit. All but three children (98.6%) were breast-fed. Although 87.1% of the mothers breast-fed their children for at least 1 y, only 3.3% of the infants were breast-fed exclusively at the age of 4 mo. In the analyses of growth, care was taken to address the biases of reverse causality, regression to the mean and confounding. There was little association between feeding pattern at 15 d and growth in length in mo 1. However, partially breast-fed and weaned infants gained weight more slowly than those exclusively or predominantly breast-fed. From 1 to 3 mo, exclusively breast-fed infants grew more quickly in both weight and length, followed by predominantly breast-fed infants. From 3 to 6 mo, exclusively breast-fed infants gained more weight compared with the other groups, but there was a slight difference (P = 0.047) in length gain only between exclusively and partially breast-fed infants. In the older period (6-12 mo), exclusively and predominantly breast-fed infants grew in length more quickly than partially breast-fed and weaned groups. However, there was no difference in weight gain among groups. Morbidity from diarrhea and acute respiratory infections was significantly lower for the >/=3 mo exclusively breast-fed group (chi(2) and Fisher-Exact Test). Over nearly the whole age range from 1 mo to 4 y, Z-scores for all indices (weight-for-age, height-for-age and weight-for-height) of the children who received complementary food were significantly lower than those of children who were exclusively breast-fed for at least 3 mo (repeated measures ANOVA, adjusted for sex, family size, maternal education and family income). These results show a long-term deterioration of physical growth in infants who received premature complementary feeding and confirm the importance of exclusive breast-feeding for infants for at least 3 mo.     

Iron supplementation affects growth and morbidity of breast-fed infants: results of a randomized trial in Sweden and Honduras

Iron supplements are often prescribed during infancy but their benefits and risks have not been well documented. We examined whether iron supplements affect growth or morbidity of breast-fed infants. Full-term infants in Sweden (n = 101) and Honduras (n = 131) were randomly assigned to three groups at 4 mo of age: 1) placebo from 4 to 9 mo; 2) placebo from 4 to 6 mo and iron supplements [1 mg/(kg. d)] from 6 to 9 mo; or 3) iron supplements from 4 to 9 mo. All infants were exclusively or nearly exclusively breast-fed to 6 mo and continued to be breast-fed to at least 9 mo. Growth was measured monthly and morbidity data were collected every 2 wk. Among the Swedish infants, gains in length and head circumference were significantly lower in those who received iron than in those given placebo from 4 to 9 mo. The same effect on length was seen in Honduras, but only at 4-6 mo among those with initial hemoglobin (Hb) > or =110 g/L. There was no significant main effect of iron supplementation on morbidity, nor any significant interaction between iron supplementation and site, but for diarrhea (with both sites combined), there was an interaction between iron supplementation and initial Hb. Among infants with Hb < 110 g/L at 4 mo, diarrhea was less common among those given iron than in those given placebo from 4-9 mo, whereas the opposite was true among those with Hb > or = 110 g/L (P < 0.05). We conclude that routine iron supplementation of breast-fed infants may benefit those with low Hb but may present risks for those with normal Hb.     

Energy utilization of breast-fed and formula-fed infants

Breast-fed and formula-fed infants (n = 65) were studied at 1 and 4 mo of age to elucidate differences in energy utilization between feeding groups. Gross energy intake at 1 mo was comparable between groups but was statistically different at 4 mo. Weight, length, and weight gain were not different between groups. Energy expenditure 0-4 h postprandially did not differ between feeding groups. Sleeping metabolic rates (SMRs) were not different but minimal observable energy expenditures standardized by weight were lower among 4-mo-old breast-fed infants (p less than 0.03). No differences were found between feeding groups in thermic effect of feeding (TEF). Activity patterns revealed that breast-fed infants slept less than formula-fed infants (p less than 0.04). Disparities in energy intake observed between breast-fed and formula-fed infants at 4 mo of age did not result in statistically significant differences in growth rate, SMR, or TEF.     

Infant growth patterns in the slums of Dhaka in relation to birth weight, intrauterine growth retardation, and prematurity

BACKGROUND: Relations between size and maturity at birth and infant growth have been studied inadequately in Bangladesh, where the incidence of low birth weight is high and most infants are breast-fed. OBJECTIVE: This study was conducted to describe infant growth patterns and their relations to birth weight, intrauterine growth retardation, and prematurity. DESIGN: A total of 1654 infants born in selected low-socioeconomic areas of Dhaka, Bangladesh, were enrolled at birth. Weight and length were measured at birth and at 1, 3, 6, 9, and 12 mo of age. RESULTS: The infants' mean birth weight was 2516 g, with 46.4% weighing <2500 g; 70% were small for gestational age (SGA) and 17% were premature. Among the SGA infants, 63% had adequate ponderal indexes. The mean weight of the study infants closely tracked the -2 SD curve of the World Health Organization pooled breast-fed sample. Weight differences by birth weight, SGA, or preterm categories were retained throughout infancy. Mean z scores based on the pooled breast-fed sample were -2.38, -1. 72, and -2.34 at birth, 3 mo, and 12 mo. Correlation analysis showed greater plasticity of growth in the first 3 mo of life than later in the first year. CONCLUSIONS: Infant growth rates were similar to those observed among breast-fed infants in developed countries. Most study infants experienced chronic intrauterine undernourishment. Catch-up growth was limited and weight at 12 mo was largely a function of weight at birth. Improvement of birth weight is likely to lead to significant gains in infant nutritional status in this population, although interventions in the first 3 mo are also likely to be beneficial.     

Mode of infant feeding and achieved growth in adolescence: early feeding patterns in relation to growth and body composition in adolescence.

OBJECTIVE: Feeding mode in infancy and differences in childhood growth have been studied in several longitudinal studies, but few studies have followed children up to adolescent age. There is evidence that formula-fed infants weigh more and are taller than their breast-fed counterparts, and indications that this difference may sustain. RESEARCH METHODS AND PROCEDURES: We have studied the relations between length of breast-feeding, growth, and body composition in a group of 781 representatively chosen adolescents. Data on feeding pattern in infancy and on weight and height from birth up to 18 years were collected. We studied the relation between high body mass index (BMI) (defined as < or =85th percentile) in adolescence and length of breast-feeding. RESULTS: Girls who were not breast-fed or breast-fed for less than 3 months had a significantly higher height curve than girls exclusively breast-fed for more then 3 months. There were tendencies towards higher values of adipose tissue measured by skinfolds in girls breast-fed for 3 months or less. Short duration of exclusive breast-feeding was associated with higher BMI (p<0.04). In a subgroup of 194 adolescents, body composition was measured with dual energy X-ray. Both boys and girls who were exclusively breast-fed for more than 3 months were leaner and showed a trend towards lower skinfold values. CONCLUSION: These results are important to include in the debate about optimal feeding in infancy. Regarding breast-feeding as a standard, our results imply that formula fed infants may be at risk for overfeeding, which might lead to overweight, even up to adolescent age.     

Stereoacuity at age 3.5 y in children born full-term is associated with prenatal and postnatal dietary factors: a report from a population-based cohort study

BACKGROUND: Observational studies suggested that breast-feeding benefits the visual development of preterm children, which has been attributed to the presence of docosahexaenoic acid (DHA) in breast milk but not most formula milks. Randomized studies showed that preterm children require a dietary supply of DHA in the first few weeks of life for optimal visual development, but it is unclear whether full-term children experience similar benefits from breast milk or DHA supplements. OBJECTIVE: The objective of this study was to compare stereoacuity at age 3.5 y in healthy, full-term children who were breast-fed and in similar children who had not been breast-fed after adjustment for socioeconomic status and maternal diet. DESIGN: Prospectively collected data on maternal diet during pregnancy (including intake of oily fish), the child's diet, and the socioeconomic status of the family were examined. Stereoacuity at age 3.5 y was assessed. RESULTS: Children who had been breast-fed for 4 mo were more likely to achieve high-grade stereopsis, or stereoscopic vision, than were children who had not been breast-fed (adjusted odds ratio: 2.77; 95% CI: 1.54, 4.97). The mother's antenatal blood DHA content was associated with her intake of oily fish (P < 0.0001). Children whose mothers ate oily fish during pregnancy were also more likely to achieve high-grade stereopsis than were children whose mothers did not eat oily fish (adjusted odds ratio: 1.57; 95% CI: 1.00, 2.45). CONCLUSIONS: The results of this study suggest that for full-term infants, breast-feeding is associated with enhanced stereopsis at age 3.5 y, as is a maternal DHA-rich antenatal diet, irrespective of later infant feeding practice.     

Iron status of infants fed low-iron formula: no effect of added bovine lactoferrin or nucleotides

BACKGROUND: The appropriate level of iron fortification in infant formula remains undetermined. OBJECTIVES: We compared hematologic indexes and iron-status indicators in infants who were either breast-fed or fed formula with concentrations of 2 or 4 mg Fe/L and evaluated the effects of providing part of the iron as bovine lactoferrin and of adding nucleotides. DESIGN: Healthy term infants were exclusively breast-fed (n = 16) or fed formula (n = 10-12) from age 4 +/- 2 wk to 6 mo. Anthropometric measures were taken monthly, and blood samples were taken at 1, 4, and 6 mo. Hematologic indexes; indicators of iron, zinc, and copper status; and erythrocyte fatty acids were assessed. RESULTS: No significant differences in hematology or iron status were observed between groups at 4 and 6 mo of age. Although 34% of all infants had a hemoglobin concentration <110 g/L at 6 mo, the absence of iron deficiency or defective erythropoiesis suggests that this hemoglobin cutoff is too high for this age group. Neither the source or the concentration of iron in formula nor fortification with nucleotides had any significant effect on serum zinc or copper, and nucleotide fortification did not affect erythrocyte fatty acids. CONCLUSIONS: A concentration of 1.6 mg Fe/L formula meets the iron requirement of healthy term infants aged 相似文献   

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.     

Progress in promoting breast-feeding, combating malnutrition, and composition and use of infant formula, 1981-2006

More than 90% of women in developing countries and 50 to 90% of women in industrialized countries now initiate breast-feeding, a marked improvement from 25 y ago. The duration of breast-feeding has lengthened, but fewer than 35% of infants worldwide are still exclusively breast-fed at 4 mo of age. Considerable progress has also been made in combating infant malnutrition. In 1980, 47% of under-5-y-old children in developing countries were stunted. This percentage declined to 29% in 2005. Major advances in formula use and composition include the introduction of formulas tailored to the perceived needs of low-birth-weight infants and the development of fortifiers to overcome the nutritional deficits of human milk for the preterm infant. More recently, postdischarge formulas were introduced and are now being used widely, often in combination with breast-feeding. Formulas for term infants also have undergone a number of changes in the past 25 y to better reproduce the composition of human milk and/or the response of the breast-fed infant. The use of whey-predominant rather than casein-predominant formulas has increased, as has the use of iron-fortified formulas. Cow's milk is introduced into the infant's diet much later than 25 y ago. Despite the progress that has been made in promoting breast-feeding and in the quality of infant formulas, further improvements in the duration of breast-feeding and in the composition of infant formulas are needed.     

Zinc during and in convalescence from diarrhea has no demonstrable effect on subsequent morbidity and anthropometric status among infants <6 mo of age

BACKGROUND: Preventing illness and improving growth in the first 6 mo of life is critical to reducing infant mortality. Zinc given for 14 d at the start of diarrhea has been shown to decrease the incidence and prevalence of diarrhea and pneumonia and improve growth in the 2-3 mo after, but no trial has been done in infants <6 mo of age. OBJECTIVE: This study sought to assess the effect of 14 d of zinc supplementation on subsequent morbidity and growth among infants 1-5 mo of age living in Pakistan, India, and Ethiopia. DESIGN: Infants with acute diarrhea were randomly assigned to receive zinc (10 mg/d; n = 538) or placebo (n = 536) for 2 wk. Weekly follow-up visits were conducted for 8 wk after the diarrhea episode. Incidence and prevalence of diarrhea and prevalence of respiratory infections including pneumonia were compared between the groups. Changes in weight, length, and corresponding z scores during the 8 wk of follow-up were also compared. RESULTS: One thousand seventy-four infants were enrolled at the start of follow-up. The groups did not differ significantly in the proportion of infants with at least one episode of diarrhea or respiratory infections. Infants who received zinc had more days of diarrhea (rate ratio = 1.20) than did the infants who received placebo. The groups had similar prevalences of pneumonia and overall respiratory infections. No significant differences in the mean changes in weight-for-age, length-for-age, and weight-for-length z scores were observed between the groups overall or in stratified analyses. CONCLUSION: Young infants do not appear to benefit from 2 wk of zinc, unlike what has been observed among older children.     

Appropriate infant feeding practices result in better growth of infants and young children in rural Bangladesh

BACKGROUND: The World Health Organization and the United Nations International Children's Emergency Fund recommend a global strategy for feeding infants and young children for proper nutrition and health. OBJECTIVE: We evaluated the effects of following current infant feeding recommendations on the growth of infants and young children in rural Bangladesh. DESIGN: The prospective cohort study involved 1343 infants with monthly measurements on infant feeding practices (IFPs) and anthropometry at 17 occasions from birth to 24 mo of age to assess the main outcomes of weight, length, anthropometric indexes, and undernutrition. We created infant feeding scales relative to the infant feeding recommendations and modeled growth trajectories with the use of multilevel models for change. RESULTS: Mean (+/-SD) birth weight was 2697 +/- 401 g; 30% weighed < 2500 g. Mean body weight at 12 and 24 mo was 7.9 +/- 1.1 kg and 9.7 +/- 1.3 kg, respectively. More appropriate IFPs were associated (P < 0.001) with greater gain in weight and length during infancy. Prior IFPs were also positively associated (P < 0.005) with subsequent growth in weight during infancy. Children who were in the 75th percentile of the infant feeding scales had greater (P < 0.05) attained weight and weight-for-age z scores and lower proportions of underweight compared with children who were in the 25th percentile of these scales. CONCLUSIONS: Our results provide strong evidence for the positive effects of following the current infant feeding recommendations on growth of infants and young children. Intervention programs should strive to improve conditions for enhancing current infant feeding recommendations, particularly in low-income countries.     

Predominant breast-feeding from birth to six months is associated with fewer gastrointestinal infections and increased risk for iron deficiency among infants

Iron deficiency (ID) is prevalent among infants world-wide and may be more likely among infants born to women living in disadvantaged environments. A strategy to address ID in this context is to feed iron-fortified formula, but this may create risk for gastrointestinal (GI) infection. Our objective was to investigate the relationship between infant feeding practices, iron status, and likelihood of a GI infection in the first 6 mo of life. We conducted a prospective study at a public hospital in Guadalajara, Mexico. Healthy women who gave birth to a healthy term infant were eligible to participate. Each month, mothers (n = 154) provided information on infant feeding methods and symptoms of GI infection. At 6 mo of age, infants' iron status was assessed [hemoglobin (Hb) and serum ferritin concentration]. When compared with nonpredominantly breast-fed [partially breast-feeding (PBF) and formula feeding (FF) combined], predominantly breast-fed (PRBF) infants to 6 mo had a lower incidence of GI infection from 0-6 mo [18 vs. 33%; P = 0.04; adjusted odds ratio (OR) = 0.4; 95% CI = 0.2, 1.0] but a higher risk for ID (serum ferritin < 12 microg/L) at 6 mo (22 vs. 4%; P = 0.001; adjusted OR = 9.2; 95% CI = 2.3, 37.0). Anemia (Hb < 110 g/L) prevalence did not differ among feeding groups (13% for PRBF, 19% for PBF, and 4% for FF; P = 0.09). In this low-income population, our results suggest that PRBF should be promoted and the risk for ID managed using public health and nutrition strategies.     

Exclusive breast-feeding of newborns among married women in the United States: the National Natality Surveys of 1969 and 1980

Questions about infant feeding practices after birth were included in 1969 and 1980 National Natality Surveys (NNS). At 3-6 mo postpartum, NNS questionnaires were mailed to mothers of live infants born in wedlock, and responses were weighted to permit national estimates. Based on the NNS, the proportion of women who were exclusively breast-feeding newborns in the United States was significantly lower in 1969 (19% of white women, 9% of black women) compared with 1980 (51% of white women, 25% of black women). In 1969, the highest percentages of exclusive breast-feeding were observed among white women less than or equal to 34 yr, of parity less than or equal to 3 and greater than 7, and of higher than lower socioeconomic groups; and among black women greater than or equal to 30 yr, of parity greater than or equal to 4, and of lower than higher socioeconomic groups. Among women in both races in 1980, more primiparae than multiparae and the more highly educated were breast-feeding. More white than black women exclusively breast-fed within each birthweight and each sociodemographic characteristic in 1980; therefore, the racial differences remained across these factors. These findings are compared with results of the Ross Laboratories surveys of infant feeding.     

Incidence and duration of breast-feeding in Mexican-American infants, 1970-1982

The Mexican-American component of the Hispanic Health and Nutrition Examination Survey (HHANES-MA) was used to examine the breast-feeding behavior of 2402 infants born between 1970 and 1982. The proportion of infants ever breast-fed increased substantially in recent years. Weighted proportions were 30.7% for 1970-1974, 38.1% for 1975-1978, and 47.6% for 1979-1982. By use of logistic regression models, children born into households with a college-educated head were shown to be more likely to be breast-fed than were other children; breast-feeding was also positively associated with birth weight. Infants in households for which the preferred interview language was Spanish were more likely to be breast-fed than were infants living in households for which the interview was conducted in English. Analysis of the factors influencing the distribution of weaning times among infants was less definitive because reported weaning times are heaped on multiples of 3 mo. The gathering of current-status, or status quo, information on infant feeding is urged for data collection in future studies.     

Vitamin supplementation of HIV-infected women improves postnatal child growth

BACKGROUND: Linear growth retardation and wasting are common in children born to HIV-infected women. Inexpensive interventions that could improve the postnatal growth pattern of such children are needed. OBJECTIVE: The objective was to examine the effect of supplementing HIV-infected women with multivitamins or vitamin A and beta-carotene, during and after pregnancy, on the growth of their children during the first 2 y of life. DESIGN: We conducted a randomized placebo-controlled trial in 886 mother-infant pairs in Tanzania. At the first prenatal visit, HIV-infected women were randomly assigned to 1 of 4 daily oral regimens in a 2 x 2 factorial fashion: multivitamins (MV: thiamine, riboflavin, vitamin B-6, niacin, vitamin B-12, vitamin C, vitamin E, and folic acid), preformed vitamin A + beta-carotene (VA/BC), MV including VA/BC, or placebo. Supplementation continued during the first 2 y postpartum and thereafter. Children were weighed and measured monthly, and all received vitamin A supplements after 6 mo of age per the standard of care. RESULTS: Multivitamins had a significant positive effect on attained weight (459 g; 95% CI: 35, 882; P = 0.03) and on weight-for-age (0.42; 95% CI: 0.07, 0.77; P = 0.02) and weight-for-length (0.38; 95% CI: 0.07, 0.68; P = 0.01) z scores at 24 mo. VA/BC seemed to reduce the benefits of MV on these outcomes. No significant effects were observed on length, midupper arm circumference, or head circumference. CONCLUSION: Supplementation of HIV-infected women with multivitamins (vitamin B complex, vitamin C, and vitamin E) during pregnancy and lactation is an effective intervention for improving ponderal growth in children.     

Food choices to meet nutritional needs of breast-fed infants and toddlers on mixed diets

The primary focus of this review is considerations for complementary feedings to meet micronutrient needs of infants aged 6-24 mo who are continuing with breast-feeding and minimal or no formula. The World Health Organization recommends initiation of complementary feeding to breast-fed infants at approximately 6 mo of age. Whether complementary foods will meet nutrient needs will depend on the types of food selected. One criterion for the selection of complementary foods is that they be rich sources of zinc and iron because both of these essential micronutrients are critical for normal growth and development, and requirements are not met by exclusive breast-feeding after approximately 6 mo. For an exclusively breast-fed 7-mo-old infant, human milk provides approximately 0.5 mg of zinc, and a little over half of that is absorbed. Adding some cereal can increase zinc intake modestly but will fall short of providing the estimated physiologic requirement because adaptive mechanisms are inadequate to compensate for moderately low zinc intake. Maize, wheat, rice, and roots are also relatively low in zinc and have the added factor of a high phytate-to-zinc molar ratio, which makes the zinc less bioavailable. Meats and liver have greater zinc and iron concentrations than unfortified plant foods and have been shown to have good acceptance by 7-mo-old infants. In contrast to current practices in both developed and developing countries, meats should be considered as an early complementary food for breast-fed infants to provide essential micronutrients.     

The prevalence of stunting is high in HIV-1-exposed uninfected infants in Kenya

As prevention of mother-to-child HIV-1 transmission (PMTCT) programs decrease the numbers of HIV-1-infected infants, it remains important to improve growth in HIV-1-exposed, uninfected (EU) infants. To determine the growth rate and predictors of growth faltering in breast-fed and formula-fed EU infants, growth analyses [weight-for-age (WAZ), weight-for-length (WLZ), and length-for-age (LAZ) Z-scores] were conducted by using data from a randomized feeding trial in HIV-1-infected women in Kenya. Growth faltering in EU infants was compared based on randomization to breastfeeding (BF) or formula feeding (FF) using Cox proportional hazards regression models. Linear mixed-effects models determined rate and cofactors of length growth. Among 338 EU infants, 164 (49%) were breast-fed and 174 (51%) formula-fed. In both arms, growth declined steadily during follow-up. By 2 y, 29% of children were underweight (WAZ < -2), 18% were wasted (WLZ < -2), and 58% were stunted (LAZ < -2), with no differences by feeding arm. Higher maternal education (y) and taller stature (cm) were associated with a decreased risk of underweight and stunting [underweight: adjusted HR (aHR) = 0.90 (95% CI: 0.83, 0.99), P = 0.03, and aHR = 0.92 (95% CI: 0.87, 0.97), P = 0.002; and stunting: aHR = 0.91 (95% CI: 0.85, 0.97), P = 0.003, and aHR = 0.96 (95% CI: 0.92, 0.99), P = 0.02, respectively]. Diarrhea was associated with an increased risk of wasting [aHR = 2.26 (95% CI: 1.11, 4.62), P = 0.03]. In multivariate analyses, FF was associated with slower declines in length velocity [0.24 LAZ/y (95% CI: 0.06, 0.43), P = 0.009]. Despite being uninfected, HIV-1-exposed infants showed frequent growth faltering, suggesting the need for vigilance in recognizing stunting within PMTCT programs. The slower rate of decline in length growth with FF may reflect benefits of micronutrients. Because BF is the best option for HIV-1-infected mothers in resource-limited settings, nutritional interventions should be examined for their impact on growth in EU breast-fed infants.     

Full breast-feeding for at least four months has differential effects on growth before and after six months of age among children in a Mexican community

This study examines the relationship between breast-feeding and growth from 0 to 6 and 6 to 20 mo among 185 children in a Mexican community. Infants from a previous 6-mo longitudinal study were followed up for additional anthropometric measurements at a mean age of 19.9 mo. Size at 6 mo and at follow-up were modeled as outcomes of whether infants were fully breast-fed (exclusively or predominantly breast-fed) for at least 4 mo, controlling for size at birth and 6 mo, respectively, and potential confounders. From birth to 6 mo, fully breast-fed infants had ponderal index increments of 0.07 units larger (P = 0.04) than comparison infants. There were no differences in weight. For length, an interaction between full breast-feeding and socioeconomic status (SES) was found, with fully breast-fed infants of low SES growing more than comparison infants, whereas the opposite was seen at upper SES levels. From 6 to 20 mo, fully breast-fed infants had weight and length increments of 0.53 cm (P < 0.001) and 0.72 kg (P = 0.01) smaller than those of comparison infants. For ponderal index, an interaction between mother's education and breast-feeding revealed an inverted U-shaped response across levels of education. Additionally, logistic regressions of monthly breast-feeding on lagged measurements revealed that relatively heavier infants had higher odds of being fully breast-fed at 2 and 3 mo. Our findings indicate that the benefits of full breast-feeding on growth may be most pronounced early in life. Further research of unmeasured confounders may explain the association of full breast-feeding with slower growth beyond 6 mo.     

The role of infant feeding practices in the explanation for ethnic differences in infant growth: the Amsterdam Born Children and their Development study

Rapid early growth in infants may influence overweight and CVD in later life. Both rapid growth and these disease outcomes disproportionately affect some ethnic minorities. We determined ethnic differences in growth rate (Δ standard deviation scores, ΔSDS) during the first 6 months of life and assessed the explanatory role of infant feeding. Data were derived from a multiethnic cohort for the Amsterdam Born Children and their Development study (The Netherlands). Growth data (weight and length) of 2998 term-born singleton infants with no fetal growth restriction were available for five ethnic populations: Dutch (n 1619), African descent (n 174), Turkish (n 167), Moroccan (n 232) and other non-Dutch (n 806). ΔSDS for weight, length and weight-for-length between 4 weeks and 6 months were defined using internal references. Infant feeding pattern (breast-feeding duration, introduction of formula feeding and complementary feeding) in relation to ethnic differences in growth rate was examined by multivariate linear regression. Results showed that the growth rate was higher in almost all ethnic minorities, with β between 0·07 and 0·41 for ΔSDS weight and between 0·12 and 0·42 for ΔSDS length, compared with ethnic Dutch infants. ΔSDS weight-for-length was similar across groups, except for Moroccan infants (β 0·25, P?相似文献   

Iron absorption in breast-fed infants: effects of age,iron status,iron supplements,and complementary foods

BACKGROUND: Iron supplements are often recommended for older breast-fed infants, but little is known about factors affecting iron absorption from human milk or supplements. OBJECTIVE: We investigated the effects of age, iron status, and iron intake on iron absorption in healthy, term, breast-fed infants. DESIGN: Twenty-five infants were randomly assigned to receive either 1) iron supplements (1 mg x kg(-1) x d(-1)) from 4 to 9 mo of age, 2) placebo from 4 to 6 mo and iron supplements from 6 to 9 mo, or 3) placebo from 4 to 9 mo. Infants were exclusively breast-fed to 6 mo and partially breast-fed to 9 mo of age. Iron absorption was assessed by giving (58)Fe with mother's milk at 6 and 9 mo. Blood samples were obtained at 4, 6, and 9 mo, and complementary food intake was recorded at 9 mo. RESULTS: At 6 mo, mean (+/-SD) fractional iron absorption from human milk was relatively low (16.4 +/- 11.4%), with no significant difference between iron-supplemented and unsupplemented infants. At 9 mo, iron absorption from human milk remained low in iron-supplemented infants (16.9 +/- 9.3%) but was higher (P = 0.01) in unsupplemented infants (36.7 +/- 18.9%). Unexpectedly, iron absorption at 9 mo was not correlated with iron status but was significantly correlated with intake of dietary iron, including supplemental iron. CONCLUSIONS: Changes in the regulation of iron absorption between 6 and 9 mo enhance the infant's ability to adapt to a low-iron diet and provide a mechanism by which some, but not all, infants avoid iron deficiency despite low iron intakes in late infancy.