Iron and the Breast-fed Infant

描述（从申请人的描述扫描）：越来越多的 婴儿享受母乳喂养的时间越来越长 时期长期母乳喂养是一个相对未知的领域， 营养的观点。铁营养是一个领域， 关心出生时的铁储备提供了正常婴儿的所有铁 在生命的前5-6个月的生长需要。但在铁商店 疲惫的婴儿依赖于铁的饮食来源。仅母乳 只提供婴儿生长所需的一小部分铁。互补 食物中有效铁的含量差别很大， 婴儿总是得到必要量的铁。之假设 长期母乳喂养会产生缺铁的风险， 试点研究。6个月大后，几个婴儿缺铁， 有些人甚至因为缺铁而贫血。提供药用铁 从1到5个半月的年龄没有改善铁的状态。我们的其他研究 单位已经表明，婴儿重新排泄到粪便中的可观数量的 吸收铁这项建议是在这些早期研究的基础上提出的。具体目标1 我们建议全面了解儿童的铁营养状况 母乳喂养的婴儿（特别是长期母乳喂养的婴儿） 期间）和补充食物，他们喂养和铁的量 它们是由此衍生的。将对1至24个月的婴儿进行纵向研究 年龄。从公共卫生的角度来看，这是迫切需要的。 信息，因为它将描述的规模和性质的 问题.同样紧迫的是需要找到预防缺铁的方法。 具体目标2的目的是探索两种不同方法的功效 铁的补充方案。一是提供药用铁（铁 另一种是每天喂一罐铁强化的 谷物和水果的组合，都从4至9个月大。我们预计这些 方案是有效的，有益的效果持续超过 补充期。具体目标3涉及以下机制： 让大多数母乳喂养的婴儿保持良好的铁状态，尽管低 母乳中的铁含量。我们也希望能解开铁为什么 在我们的初步研究中，补充剂对幼儿无效。我们 将使用铁的两种稳定（非放射性）同位素来确定吸收 母乳喂养的婴儿在4个月和9个月大时的铁排泄量， 有和没有铁补充剂。我们希望发现婴儿 当铁储存满时，它们将铁重新排泄到粪便中，但保留大部分铁。 当铁含量低时，吸收的铁。

DESCRIPTION (Scanned from the applicant's description): Increasing numbers of infants are enjoying the benefits of breast feeding for longer and longer periods. Prolonged breast feeding is relatively uncharted territory from a nutritional point of view. Iron nutrition is one area where there has been concern. Iron stores present at birth provide all the iron the normal infant needs for growth during the first 5-6 months of life. But after iron stores are exhausted the infant depends on a dietary source of iron. Breast milk alone provides only a fraction of the iron the infant needs for growth. Complementary foods vary widely in content of available iron, and it appears unlikely that infants always receive the necessary amounts of iron. The presumption that prolonged breast feeding engenders a risk of iron deficiency was born out by a pilot study. After 6 months of age several infants became iron deficient and some even became anemic due to iron deficiency. Provision of medicinal iron from 1 to 5 1/2 months of age did not improve iron status. Other studies in our unit have shown that infants re-excrete into the stool appreciable amounts of absorbed iron. This proposal builds on these earlier studies. In Specific Aim 1 we propose to generate a broad picture of the iron nutritional status of breast-fed infants (specifically, infants who are breast-fed for prolonged periods) and of the complementary foods they are fed and the amount of iron they derive thereof. Infants will be studied longitudinally from 1 to 24 months of age. From a public health point of view there is an urgent need for this information because it will delineate the magnitude and the nature of the problem. Equally urgent is the need to find ways of preventing iron deficiency. The objective of Specific Aim 2 is to explore the efficacy of two different regimens of iron supplementation. One is the provision of medicinal iron (iron drops), the other is the feeding of one jar per day of an iron-fortified cereal-fruit combination, both from 4 to 9 months of age. We expect these regimens to be effective and the beneficial effects to persist beyond the supplementation period. Specific Aim 3 is concerned with the mechanisms that allow most breast-fed infants to remain in good iron status despite the low iron content of breast milk. We also hope to solve the puzzle why iron supplementation was ineffective in the young infants in our pilot study. We will use two stable (non-radioactive) isotopes of iron to determine absorption and excretion of iron by breast-fed infants both at 4 and 9 months of age and with and without iron supplementation. We expect to find that infants re-excrete iron into the feces when their iron stores are full, but retain most of the absorbed iron when iron stores are low.