EVALUATION OF MINERAL ABSORPTION IN INFANTS FED HUMAN MILK OR FORMULA

母乳或配方奶喂养婴儿矿物质吸收的评估

• 批准号: 7374962
• 负责人: STEVEN A ABRAMS
• 金额: $ 0.16万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-12-01 至 2006-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7374962
• 关键词: EVALUATION; MINERAL; ABSORPTION; INFANTS; FED

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Enfamil and Enfamil Lipil are rich in palm olein, with a fat blend comprised on 40% palmitic acid and 43% oleic acid. However, in contrast to human milk, the palmitic acid in vegetable oils is predominantly esterified in the sn-1 and sn-3 position rather than the sn-2 position (1), as is the case for palmitic acid found in human milk (2,3). Palmitic acid that is esterified in the sn-1 and sn-3 position tends to be hydrolyzed during digestion and made available to form insoluble calcium soaps, resulting in poorer fat and calcium absorption than is seen with formulas with less palmitic in the sn- 1 and sn-3 position (4-6). Whether the inclusion of interesterified palm olein (with greater palmitic acid in the sn-2 position) in an Enfamil formulation would results in better fat and calcium absorption than the current formulation is not known. Moreover, whether calcium absorption in the current Enfamil formulation is similar to that provided by human milk has not been studied directly. The formula on the market now, like many infant formulas, has the palmitic acid predominantly esterified in the sn-1 and sn-3 position rather than the sn-2 position, as is the case for palmitic acid found in human milk. The second formula has more palmitic acid in the sn-2 position (less in the sn-1 and sn-3 positions), making it more comparable to human milk. As it is even closer in composition to human milk, we consider it to be a safe product and are merely assessing the effect on calcium absorption. From an FDA level, this change is considered minor and does not, for example, require the full set of research studies to allow the change as would be needed for a major change. Finally, previous tolerance studies have been done to demonstrate the safety of the formula. Since modifications and improvements of formulations have been guided by the nutrient content and functional nutrient composition of human milk, it is important that Mead Johnson Nutritionals (MJN) confirm the functional adequacy of Enfamil Lipil compared to human milk. The mean published absorption of calcium from breast milk is 58 +/- 17% with a mean calcium content of 41 mg/100 kcal, yielding a daily calcium absorption of 24.6 +/- 15 (SD) mg/100 kcal. The higher calcium content of Enfamil (78 mg/100 kcal) actually compensates for less fractional calcium absorption (38 +/- 16%). Therefore daily calcium absorption is 29.6 +/- 12.5 mg/100 kcal. All of these values reflect values generated using classic balance techniques rather than dual stables isotopes. Previous studies have shown that by using dual isotope absorption methods we can expect SD for Enfamil Lipil of 8 rather than 12.5 and SD values for Enfamil Lipil with interesterified palm olein fat blend (IPO-EL) of about 40 +/- 10. In contrast to formula, human milk calcium content also varies significantly between mothers in addition to variation in measured fractional absorption, which would be expected to be more similar between groups. Thus, the wider classical balance for absolute calcium absorption from human milk was pooled with the estimated double isotope method variance from the formulas (standard deviations of 15, 8, and 10) to estimate the population variance of 11.4 to calculate the n needed for this study to provide 80% power with an alpha level of 0.05.

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。安非米和安非明LIPIL含有丰富的棕榈油，脂肪混合物含有40%的棕榈酸和43%的油酸。然而，与人奶不同的是，植物油中的棕榈酸主要是在sn-1和sn-3位置上酯化，而不是像人奶中发现的棕榈酸那样在sn-2位置(1)上酯化(2，3)。在sn-1和sn-3位酯化的棕榈酸在消化过程中容易被水解，并可形成不溶性钙皂，导致脂肪和钙的吸收比在sn-1和sn-3位较少棕榈酸的配方(4-6)更差。目前尚不清楚在安非米配方中加入酯交换棕榈油(在sn-2位含有较大的棕榈酸)是否会导致比目前配方更好的脂肪和钙吸收。此外，目前的安非米配方中的钙吸收是否类似于母乳提供的钙吸收还没有直接研究。像许多婴儿配方奶粉一样，现在市场上的配方奶粉中的棕榈酸主要是在sn-1和sn-3位置上酯化，而不是像在母乳中发现的棕榈酸那样在sn-2位置上酯化。第二种配方在sn-2位含有更多的棕榈酸(在sn-1和sn-3位较少)，使其更接近于人奶。由于它的成分更接近人奶，我们认为它是一种安全的产品，只是在评估其对钙吸收的影响。从FDA的层面来看，这一变化被认为是微小的，例如，不需要像重大变化所需的那样，进行全套研究来允许这种变化。最后，之前的耐受性研究已经证明了该配方的安全性。由于配方的修改和改进一直以母乳的营养含量和功能性营养成分为指导，美赞臣营养品(MJN)确认安非米LIPIL与母乳相比功能充足是很重要的。已公布的母乳钙平均吸收率为58+/-17%，平均钙含量为41毫克/100千卡，每日钙吸收率为24.6+/-15(SD)毫克/100千卡。较高的钙含量(78毫克/100千卡)实际上弥补了较少的钙吸收分数(38+/-16%)。因此，每天的钙摄入量为29.6+/-12.5毫克/100千卡。所有这些值都反映了使用经典平衡技术而不是双稳定同位素产生的值。以前的研究表明，通过使用双同位素吸收方法，我们可以预期安非他明LIPIL的SD值为8而不是12.5，而安非他明LIPIL与酯交换棕榈油脂肪混合物(IPO-EL)的SD值约为40+/-10。与配方奶粉相反，母乳钙含量在不同母亲之间也有很大差异，除了测量的吸收分数不同，预计组间更相似。因此，从母乳中绝对钙吸收的更广泛的经典平衡与公式中估计的双同位素方法方差(标准差为15、8和10)合并在一起，估计总体方差为11.4，以计算本研究所需的n，以提供α水平为0.05的80%功率。