Early infant feeding and growth status of US-born infants and children aged 4-71 mo: analyses from the third National Health and Nutrition Examination Survey, 1988-1994

BACKGROUND: There is controversy over what growth references to use in evaluating breast-fed infants and concern about whether never-breast-fed infants are at risk of overweight in childhood. OBJECTIVE: The objective of this study was to determine whether infants who are exclusively breast-fed for 4 mo differ in average size from infants who are fed in other ways and whether such differences persist through age 5 y. DESIGN: Data from the third National Health and Nutrition Examination Survey (NHANES III) were linked to birth certificates of US-born infants and children. Feeding groups were defined on the basis of feeding patterns over the first 4 mo of life: exclusively breast-fed for 4 mo, partially breast-fed, breast-fed for <4 mo, and never breast-fed. Growth status, indexed as internally derived z scores (SD units) for weight, length (height), weight-for-length (height), midupper arm circumference, and triceps skinfold thickness, was compared among feeding groups. RESULTS: The final sample consisted of 5594 non-Hispanic white, non-Hispanic black, and Mexican American infants and children aged 4-71 mo. Of these, 21% were exclusively breast-fed for 4 mo, 10% were partially breast-fed, 24% were breast-fed for <4 mo, and 45% were never breast-fed. At 8-11 mo, infants who were exclusively breast-fed for4 mo had adjusted mean z scores for weight (-0.21; -0.2 kg), weight-for-length (-0.27), and midupper arm circumference (-0.15) that differed significantly from zero (P < 0. 05). By 12-23 mo, the differences had dissipated; there were no significant differences subsequent to 5 y. Triceps skinfold thickness was not related to early infant feeding. CONCLUSION: Infants who were exclusively breast-fed for 4 mo weighed less at 8-11 mo than did infants who were fed in other ways, but there were few other significant differences in growth status through age 5 y associated with early infant feeding.     

Catch-up growth in small-for-gestational-age term infants: a randomized trial

BACKGROUND: Small-for-gestational-age (SGA) term infants are at risk of long-term growth deficits. OBJECTIVE: The objectives were to test the hypothesis that postnatal growth in SGA term infants can be altered by dietary intervention and to examine whether there is a critical window for nutritional programming of the growth trajectory during the first 9 mo postnatally. DESIGN: Healthy term (gestation > or =37 wk) infants with birth weights below the 10th centile were randomly assigned to receive standard term formula (TF; n = 147) or nutrient-enriched formula (EF; n = 152) for the first 9 mo; 175 breast-fed SGA term infants formed a reference group. The main outcome measures were weight, length, and occipitofrontal head circumference (OFC) at 9 and 18 mo. RESULTS: The infants fed the EF showed greater gains in length by 9 (1.1 cm; 95% CI: 0.38, 1.79) and 18 (1.0 cm; 0.25, 1.83) mo and in OFC by 9 (0.5 cm; 0.1, 0.9) and 18 (0.6 cm; 0.2, 1.1) mo than did infants fed the TF; the differences were larger in females. The dietary effects were independent of the pattern of growth retardation. Breast-fed infants showed greater gains in weight and OFC by 18 mo than did infants fed the TF; however, these differences disappeared after adjustment for age, parental size, and birth order. CONCLUSIONS: Linear growth and OFC gains in SGA term infants improve after nutritional intervention during the first 9 mo of life and the effects persist for > or =9 mo beyond the intervention period. Further information on whether catch-up growth is beneficial or detrimental to long-term outcomes is required before public health interventions can be recommended.     

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.     

Determinants of infant growth in the slums of Dhaka: size and maturity at birth, breastfeeding and morbidity

OBJECTIVE: To investigate the influences of size at birth, breastfeeding and morbidity on growth during infancy in poor areas of urban Bangladesh. DESIGN: This was a prospective observational study of a cohort of newborn infants followed until 12 months of age. SETTING: Slum areas of Dhaka City in Bangladesh. SUBJECTS: A total of 1654 newborn infants were enrolled at birth, and follow-up was completed for 1207 infants. Repeated anthropometric measurements and interviews of caretakers on infant feeding and morbidity were conducted. A mixed effects regression method was used for modeling infant growth. RESULTS: After adjusting for other variables, mean differences in body weight by birth weight and length, small-for-gestational age and prematurity categories remained relatively constant throughout infancy. A positive impact of exclusive breastfeeding in the first 3 5 months on infant growth was detectable at 12 months of age. Although the bigger babies in the sample tended to grow relatively even bigger; exclusive breastfeeding appeared to counteract this pattern. Reported diarrhoea was associated with lower body weights and lengths even after adjusting for feeding patterns. CONCLUSIONS: Size at birth has an important role in determining growth during infancy. Effective strategies for improving birth weight, poorly addressed till now in Bangladesh, are needed. The sustained effect on growth and the even more beneficial effect in lighter infants are compelling reasons for promotion of exclusive breastfeeding in early infancy.     

低出生体重早产儿0～2岁追赶生长的纵向随访研究

目的 分析低出生体重早产儿生后2年内的生长模式及特点,以促进早产儿适宜的体格生长。方法 2012年1月-2015年12月选取青岛大学附属医院儿童保健科规律随访和管理的低出生体重早产儿123例,分为小于胎龄(SGA)儿和适于胎龄(AGA)儿,定期测量体重、身长、头围等数据,采用WHO Anthro软件,计算生后3、6、12、24月龄的体重、身长和头围Z 评分。采用重复测量资料方差分析比较不同特征早产儿生长指标情况。结果 1)早产儿总体体重、身长及头围在生后12个月内Z评分呈上升趋势,但在12~24月龄间Z评分上升不明显。2)SGA与AGA比较,组内效应分析显示:两组体重、身长、头围Z评分总体表现为上升趋势,增长速度以6月龄之前最快,后增速放缓,SGA组身长Z评分在12月龄后转为下降趋势。组间效应显示:在3~24月龄期间,SGA组生后各年龄组体重、身长及头围Z评分值均小于AGA组,差异有统计学意义(F=5.653、5.644、 7.163,P＜0.05)。AGA组在12、24月龄时体重、身长、头围接的评分接近于WHO标准同龄儿童的均值水平。结论 低出生体重早产儿在生后24个月内体重、身长和头围均有追赶生长,追赶生长主要发生在生后12个月内,呈先快后慢的模式,SGA 早产儿各月龄体格生长情况均低于AGA 早产儿。     

低出生体重儿保健管理的效果

目的 探讨低出生体重儿体重,身高增长的速度及差异,了解干预效果。方法 对１０１例低出生体重儿从出生随访至３６个月,采用ＮＣＨＳ标准,用Ｚ评分方法进行评价和综合干预,与１９例未经干预的低出生体重儿进行比较。结果 １０１例低出生体重儿出生体重ＳＤＳ值〈－２ｓ的比例随着年龄５的增长逐渐降低,到３６个月９８％达正常范围且ＳＤＳ值明显优于对照组。     

广州市社区足月小样儿 0~2岁体格发育的纵向研究

目的 了解足月小样儿生后2年内的体格发育和营养状况,为制定足月小样儿生长发育干预策略提供科学依据。方法 采用前瞻性的研究方法,选取2016年1月—2018年4月广州出生的足月小样儿为小于胎龄儿(SGA)组,选取同种族、同社区、同年龄的足月正常体重儿为适于胎龄儿(AGA)组,定期对生长参数进行了纵向评估,比较两组儿童体格发育特点。结果 1) SGA组生后各年龄组体重和身长Z评分均小于AGA组,但生后第一年Z评分呈上升趋势,体重增长(△Z评分为1.17±1.10)、身长增长(△Z评分为0.65±1.23)均大于AGA组。2) 67.65%和50.98% 的SGA在婴儿期出现体重和身长追赶生长;婴儿期生长速率与2岁时营养状况相关(P<0.01)。3) SGA组在各年龄的低体重、生长迟缓、消瘦率均高于AGA组,2岁时发生率在8%~15%。超重和肥胖率低于AGA组,2岁时超重率为2.94%。两组间低体重、生长迟缓和超重率比较,差异有统计学意义(χ²=4.40、4.18、5.38,P<0.05); SGA组6月龄贫血患病率高达43.63%。结论 足月小样儿生后一年内体重和身长均有追赶生长。营养不良发生状况不容忽视,应注意预防足月小样儿营养不良和6月龄贫血。     

Breast and complementary feeding practices in relation to morbidity and growth in Malawian infants

OBJECTIVES: The objective of this study was to compare growth, morbidity incidence and risk factors for undernutrition between infants receiving complementary feeding early, before 3 months of age, with those receiving complementary foods after 3 months in a poor rural Malawian community. METHODS: A cohort of babies was enrolled at birth for follow-up to 12 months of age. Weight, length, morbidity and feeding patterns were recorded at 4 weekly intervals from birth to 52 weeks. RESULTS: Mean age at introduction of water was 2.5 months (range 0-11.8), complementary foods 3.4 months (range, 1.0-10.7) and solids 4.5 months (range 1.2-13.8). Over 40% of infants had received complementary foods by 2 months and 65% by 3 months. The proportion of exclusively breast-fed infants, which included those receiving supplemental water, was 13% at 4 months, 6.3% at 5 months and 1.5% at 6 months. Infants with early complementary feeding had lower weight for age at 3 and 6 months (P<0.05), and at 9 months (P=0.07) and at 2 months they were approximately 200 g lighter. Early complementary feeding was significantly associated with increased risk for respiratory infection (P<0.05), and marginally increased risk for eye infection and episodes of malaria. Maternal illiteracy was associated with early complementary feeding (OR=2.1, 95% CI 1.3, 3.2), while later complementary feeding was associated with reduced infant morbidity and improved growth. CONCLUSION: Breast-feeding promotion programmes should target illiterate women. Greater emphasis is required to improve complementary feeding practices.     

不同出生体重早产儿2岁内追赶生长特征的纵向研究

目的 分析早产儿2岁以内体格追赶生长特征,为早产儿临床干预提供资料。方法 选择2017年1月—2019年6月在长沙市妇幼保健院出生至24月龄定期预约随访管理的早产儿为研究对象。采用Z评分法,对早产儿体重、身长和头围进行评估,分组统计各月龄3项指标Z值和增长值、不同Z值水平构成比与追赶生长率,分析小于胎龄儿(SGA)与适于胎龄儿(AGA)早产儿体格追赶生长特点。结果 AGA早产儿出生时、1月、18月、24月体重Z值均数,1月、9月、18月、24月身长Z值均数均高于SGA早产儿,24月头围Z值均数高于SGA早产儿(t=1.998～6.383,P＜0.05)。两组早产儿体重、身长、头围Z值均数均随月龄增长而增大,追赶速度则随月龄递增而变小,1～6月龄追赶速度最快。两组早产儿体重、身长、头围Z值＜-2的百分比均随月龄增长而下降,追赶率则随月龄增长而上升,上升幅度最大的月龄是1～6月。SGA、AGA早产儿体重出现全部追赶生长的月龄分别是18月、12月,身长、头围出现全部追赶生长的月龄均为24月。Z值≥0百分比均随月龄增长呈上升趋势,SGA早产儿体重、身长、头围24月龄时完成追赶生长百分比分别为36.1％、25.0％与22.2％,AGA早产儿24月龄时完成追赶生长百分比分别为57.7％、45.1％与43.7％。结论 低出生体重早产儿2岁内体格追赶生长具有先快后慢、体重追赶生长月龄提前等特征,追赶速度最快为1～6月龄。SGA早产儿生长水平落后于AGA早产儿。到24月龄时,除了AGA早产儿体重有超半数完成追赶生长外,其余指标完成追赶生长的个体均未超过半数。     

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.     

Is Maternal Smoking during Early Pregnancy a Risk Factor for All Low Birth Weight Infants?

Background

Low birth weight (LBW) infants do not form a homogeneous group; LBW can be caused by prematurity or poor fetal growth manifesting as small for gestational age (SGA) infants or intrauterine growth retardation. We aimed to clarify the relationship of maternal smoking with both SGA and preterm LBW infants.

Methods

The study population comprised pregnant women who registered at the Koshu City between January 1, 1995, and December 31, 2000, and their children. We performed multivariate analyses using multiple logistic regression models to clarify the relationship of maternal smoking during pregnancy with the SGA outcome and preterm birth in LBW infants.

Results

In this study period, 1,329 pregnant women responded to questionnaires, and infant data were collected from 1,100 mothers (follow-up rate: 82.8%). The number of LBW infants was 81 (7.4%). In this cohort, maternal smoking during early pregnancy was associated with LBW and the SGA outcome. Maternal smoking during early pregnancy was a risk factor for LBW with SGA outcome and for LBW with full-term birth. However, it was not a risk factor for LBW with appropriate weight for gestational age (AGA) and LBW with preterm birth.

Conclusion

These results suggested that LBW with AGA and LBW with preterm birth were associated with other risk factors that were not considered in this study, such as periodontal disease. For the prevention of LBW, not only abstinence from smoking during pregnancy but also other methods such as establishing a clinical setting should be adopted.Key words: Infant, Low Birth Weight; Pregnancy; Risk Factors; Smoking     

宫内发育迟缓对早产儿体格发育的影响

目的 探讨宫内发育迟缓对早产儿体格发育的影响,为早期干预提供科学依据。方法 将2015-2017年在西安市第四医院出生并在儿童保健科建立专案管理的符合入组条件的449例早产儿、作为观察组,其中小于胎龄(SGA)儿91例,适于胎龄(AGA)儿358例;同期随机抽取300名足月儿作为对照组,并对三组儿童进行体格发育监测及个体化喂养指导,随访至纠正12月龄,分析SGA组与AGA组后期生长发育迟缓发生率以及三组儿童生长速率之间是否存在不同。 结果 1)早产儿生后不同月龄体重、身长、头围生长发育迟缓发生率差异有统计学意义,并随月龄的增加呈下降趋势(χ²_SGA=24.242,46.761,9.891,P<0.05;χ²_AGA=17.536,45.763,13.829,P<0.05);2)相同月龄SGA组与AGA组体重、身长、头围生长发育迟缓发生率之间差异有统计学意义(P<0.05);3)纠正6个月以内SGA组、AGA组、足月儿组三组之间生长速率比较,差异有统计学意义(P<0.05)。结论 早产儿生后呈追赶性生长,SGA早产儿的追赶趋势最强,但有20%的SGA早产儿在1岁时仍存在体格发育迟缓。     

50例超低出生体重儿追赶生长的临床研究

目的研究超低出生体重儿住院期间及出院后随访阶段追赶生长的情况。方法回顾性分析本院2005年1月1日-2014年12月31日存活出院的超低出生体重儿住院期间及出院后随访资料,评价体格生长参数及不同随访阶段生长迟缓发生率。结果十年间存活出院并规律随访至校正月龄6个月以上的超低出生体重儿50例。住院期间平均体重增长速度(17.9±2.8)g/(kg·d)。出院时体重、身长、头围Z评分均较出生时Z评分明显降低。生长迟缓比例最低的时期为校正月龄0~3个月,以体重、身长、头围计算分别为20%,26%和22%,至校正月龄24个月,生长迟缓比例又出现升高趋势。根据出生时是否为SGA,胎龄(≤28周和28周),出生体重(≤750g和750g)及出生时间段(2004-2009年和2010-2014年)分组比较校正月龄满6个月及24个月的生长迟缓发生率,SGA组及胎龄大于28周组校正月龄6个月时生长迟缓率明显高于对应组,校正月龄24个月时出生体重≤750g,以头围计的生长迟缓率高于出生体重750g组。结论本组超低出生体重儿宫内生长迟缓的比例较高,至出院时又表现出更多的宫外生长迟缓。经过近年来积极的营养支持及出院后喂养干预及指导,多数早产儿在校正月龄3个月内完成体重的追赶性生长。SGA及出生体重≤750g的超低出生体重儿可能更容易发生生长迟缓。     

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.     

Growth outcome of the very low-birth-weight infant at one year

Growth patterns of weight, length, and OFC complete through 12 months corrected age were determined for 122 VLBW infants who weighed 1,500 gm. or less and were 35 weeks or less gestational age at birth. Significant differences in growth were apparent when infants were grouped according to sex and appropriateness of intrauterine growth. When the mean values of each group were compared, the female AGA infants demonstrated growth at higher percentiles (NCHS term infant norms) for all three growth parameters (weight, length, and OFC). AGA male, SGA male, and SGA female infants all grew similarly, at lower percentiles for weight and length, when compared with the same norms. Growth in OFC was closest to term infant norms in all subgroups of infants. (formula; see text) Appropriateness of weight for length was determined for each of the infants at one year corrected age. The majority of the babies, regardless of subgroup, achieved weights and lengths greater than the 5th percentile and with normal weights for lengths. At 12 months corrected age, 30% remained below the 5th percentile in weight, 21% below the 5th percentile in length, and 14% below the 5th percentile in OFC. Eighteen infants (15%) demonstrated a disproportionately low weight for length (less than the 5th percentile).     

Nutritional transition during infancy in East Java, Indonesia: 2. A longitudinal study of growth in relation to the intake of breast milk and additional foods

Weight and length of infants, born in two villages in Madura, East Java were measured longitudinally from birth to 12 months (n = 391). In a sub-sample (n = 76) the intake of breast milk and additional foods during 48 h were also measured. The shape of the weight curve of Madurese infants is comparable to that of healthy, exclusively breast-fed infants in the UK and US during the first 6 months of life, in spite of the custom to force-feed from as early as the first week. The use of a more 'appropriate' growth curve of exclusively breast-fed, healthy infants instead of the NCHS reference failed to define more accurately the age at which growth faltering starts. It is recommended to use weight increments as an indicator of the onset of growth faltering. Breast milk intake correlated significantly with attained weight. However, it explains only a small percentage of the variation in weight, viz. 12-24 per cent. There was no correlation between energy or protein intake from breast milk and additional foods and weight gain.     

Association of infant feeding practices in the general population with infant growth and stool characteristics

This was a prospective cohort study of 976 infants from birth to 12 months of age. Infants were fed breast milk, goat infant formula, cow infant formula, or a combination of formula and breast milk during the first 4 months of age. Data on type of milk feeding and infant growth (weight and height) were collected at birth and at 4, 8, and 12 months during routine clinical assessment. The number and consistency of bowel motions per day were recorded based on observational data supplied by the mothers. Infants fed breast milk or goat or cow infant formula during the first 4 months displayed similar growth outcomes. More of the infants fed cow infant formula had fewer and more well-formed bowel motions compared with breast-fed infants. The stool characteristics of infants fed goat formula resembled those of infants fed breast milk.     

出生体重对1~18月龄婴幼儿体格发育的影响

目的探讨出生体重对1~18月龄婴幼儿体格发育的影响。方法应用回顾性队列研究方法,收集2018年1月至2019年12月在广州市花都区妇幼保健院出生及进行体格检查的婴幼儿资料。不同出生体重组婴幼儿1~18月龄的体重、身长及重量指数(PI)变化的差别以及趋势分别采用单因素协方差分析以及Mann-Kendall趋势检验。广义估计方程模型用于估计出生体重对1~18月龄婴幼儿体重、身长及PI变化的影响。结果本研究共纳入1937名婴儿,其中男婴1063名(54.88%);出生体重平均(3.18±0.42)kg,小于胎龄儿(SGA)发生率为7.95%,大于胎龄儿(LGA)发生率为5.01%。随着月龄增长,SGA、适于胎龄儿(AGA)、LAG的体重/身长增量均呈增加趋势(均P<0.01),而PI增量则均呈减少趋势(均P<0.01)。在调整相关协变量后,SGA、AGA、LAG 6~18月龄的体重增量、1~18月龄的身长增量及1月龄的PI增量差异有统计学意义(P<0.05或P<0.01)。广义估计方程模型结果显示,与AGA相比,SGA的体重增量(β=-0.15)、身长增量(β=-0.79)、PI增量(β=-0.03)均较少,LGA的身长增量(β=0.78)较多。结论出生体重对1~18月龄婴幼儿体格发育有影响。医护人员应做好母亲孕期保健及产后婴幼儿的膳食营养指导,加强早期生长监测和干预,提高婴幼儿发育质量。     

Extent of thermal processing of infant formula affects copper status in infant rhesus monkeys

BACKGROUND: Infant rhesus monkeys are excellent models in which to study the effect of infant formulas on trace element absorption and status. Infants fed powdered formula from birth exhibit normal growth and have blood variables similar to those of breast-fed infants. OBJECTIVES: The objectives were to evaluate the effects of feeding ready-to-feed (RTF) formulas exposed to different heat treatments to infant monkeys, and, for one of these formulas, to compare the effect of fortification with 2 iron concentrations. DESIGN: From birth to age 5 mo, infant monkeys (n = 6/group) were fed one of the following formulas exclusively: 1) 12 mg Fe/L processed in cans (RTF-12), 2) formula in glass bottles with 12 mg Fe/L and manufactured by an ultrahigh-temperature (UHT) process (UHT-12), or 3) formula manufactured by a standard thermal process (STP), containing either 8 (STP-8) or 12 (STP-12) mg Fe/L. All formulas had similar copper concentrations (0.6 mg Cu/L). Anthropometric measures and venous blood samples were taken monthly. RESULTS: Weight and length gain did not differ among groups; however, the STP-12 group weighed less than the UHT-12 group at ages 2, 4, and 5 mo. Hemoglobin values were significantly lower in the RTF-12 group than in all other groups at ages 4 and 5 mo and serum ferritin was lower in the RTF-12 group than in the STP-12 group at age 5 mo. Copper status was lower in STP-12 infants than in STP-8 infants. There was a progressive and significant decline in plasma copper, ceruloplasmin, and Cu/Zn superoxide dismutase activity in infants fed canned formula (RTF-12). Furthermore, coat color changed from normal brown to silver. These outcomes suggest that the canned formula induced copper deficiency in infant monkeys. CONCLUSIONS: Excessive heat treatment of formula can have a pronounced negative effect on copper status. High iron concentrations did not improve iron status but may adversely affect copper status.     

Exchangeable zinc pool size at birth is smaller in small-for-gestational-age than in appropriate-for-gestational-age preterm infants

BACKGROUND: Small-for-gestational-age (SGA) infants are susceptible to postnatal zinc deficiency, but whether this susceptibility is due to intrauterine factors or to high postnatal growth requirements is unknown. OBJECTIVE: We hypothesized that the size of the exchangeable zinc pool (EZP), which reflects metabolically available zinc, would be smaller in SGA than in appropriate-for-gestational-age (AGA) infants born prematurely. DESIGN: Intravenous 70Zn (45 microg/kg) was administered to 10 SGA infants (8 boys) with a mean (+/-SD) gestational age of 33.3 +/- 1.8 wk and to 11 AGA infants (8 boys) with a mean (+/-SD) gestational age of 32.4 +/- 1.2 wk within 24 h of birth. The EZP was determined from isotope enrichment in spot urine collections on days 3-7. RESULTS: The mean birth weight of the SGA infants was 1.30 +/- 0.2 kg and of the AGA infants was 1.84 +/- 0.3 kg (P = 0.0001). The EZP size was significantly smaller in the SGA than in the AGA infants on an absolute basis (13.3 +/- 2.8 and 25.2 +/- 8.1 mg; P = 0.0002) and relative to body weight (10.3 +/- 2.5 and 13.9 +/- 4.5 mg/kg; P = 0.02). The difference remained significant after adjustment for gestational age and birth weight. CONCLUSION: These data provide evidence for differential zinc status at birth between SGA and AGA infants born prematurely at similar stages of gestation and offer at least a partial explanation for the reported benefits of postnatal zinc supplementation.