Martinez C, Fox T, Eagles J, Fairweather-Tait S
Institute of Food Research, Norwich Laboratory, Norfolk, United Kingdom.
J Pediatr Gastroenterol Nutr. 1998 Oct;27(4):419-24. doi: 10.1097/00005176-199810000-00011.
Nutritional iron deficiency in infants over 4 months of age is one of the most common deficiency disorders. Dietary iron is comprised of non-haem and haem iron, the latter being absorbed by a separate pathway and more efficiently than non-haem iron. Fortification of infant weaning foods is one of the strategies adopted for preventing iron deficiency and the aim of this project was to examine the potential use of haem iron concentrate as a fortificant.
Sixteen non-anaemic 6-month old infants were recruited and allocated to two groups of 8. Each infant consumed 2 meals/day of a commercial weaning food (100 g) for 7 consecutive days containing 40 mg ascorbic acid and 2.5 mg haem iron/100 g (Group 1) or the same quantity of iron as ferrous sulphate plus 40 mg ascorbic acid (Group 2). Bioavailability was assessed by chemical balance using carmine to mark the beginning and end of the faecal collection. The effect of haem iron concentrate (as a candidate for the factor in meat that enhances iron absorption) was examined by measuring its effect on 57Fe-labelled non-haem iron absorption.
There was no difference in iron balance between the two groups. Mean iron retention was 3.5 (SD 2.1) mg/day in Group 1 (haem iron) and 3.0 (SD 2.4) mg/day in Group 2 (ferrous sulphate). Haem concentrate did not enhance the absorption of 57Fe-labelled non-haem iron, Group 1: 1710 (SD 11.1)%, Group 2: 28.4 (SD 17.7)%.
Haem iron concentrate appears to be a highly bioavailable form of iron when added to infant weaning foods. This protein is not, however, responsible for the enhancing effect of animal protein on non-haem iron absorption.
4个月以上婴儿的营养性缺铁是最常见的营养缺乏症之一。膳食铁由非血红素铁和血红素铁组成，后者通过独立途径吸收，且比非血红素铁更有效。强化婴儿断奶食品是预防缺铁所采用的策略之一，本项目的目的是研究血红素铁浓缩物作为一种强化剂的潜在用途。
招募16名6个月大的非贫血婴儿，分为两组，每组8名。每名婴儿连续7天每天食用2餐（100克）市售断奶食品，其中一组食品每100克含40毫克抗坏血酸和2.5毫克血红素铁（第1组），另一组食品含有等量的硫酸亚铁铁加40毫克抗坏血酸（第2组）。通过化学平衡法评估生物利用度，使用胭脂红标记粪便收集的开始和结束。通过测量血红素铁浓缩物对57Fe标记的非血红素铁吸收的影响，来研究其（作为肉类中增强铁吸收因子的候选物）的作用。
两组之间的铁平衡没有差异。第1组（血红素铁）的平均铁保留量为3.5（标准差2.1）毫克/天，第2组（硫酸亚铁）为3.0（标准差2.4）毫克/天。血红素浓缩物并未增强57Fe标记的非血红素铁的吸收，第1组：17.10（标准差11.1）%，第2组：28.4（标准差17.7）%。
当添加到婴儿断奶食品中时，血红素铁浓缩物似乎是一种生物利用度很高的铁形式。然而，这种蛋白质对动物蛋白增强非血红素铁吸收的作用并无影响。
