Krebs Nancy F
University of Colorado Health Science Center, Department of Pediatrics, Denver, CO 80262-0001, USA.
J Nutr. 2007 Feb;137(2):511S-517S. doi: 10.1093/jn/137.2.511S.
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.
本综述的主要重点是关于补充喂养的考量,以满足6至24月龄继续母乳喂养且极少或不食用配方奶的婴儿的微量营养素需求。世界卫生组织建议在大约6月龄时开始对母乳喂养的婴儿进行补充喂养。补充食物能否满足营养需求将取决于所选择食物的种类。选择补充食物的一个标准是它们富含锌和铁,因为这两种必需的微量营养素对正常生长发育至关重要,且在大约6月龄后仅靠母乳喂养无法满足需求。对于纯母乳喂养的7月龄婴儿,母乳提供约0.5毫克锌,其中略多于一半可被吸收。添加一些谷物可适度增加锌的摄入量,但仍无法满足估计的生理需求,因为适应机制不足以补偿适度低锌摄入。玉米、小麦、大米和根茎类食物的锌含量也相对较低,且植酸与锌的摩尔比很高,这使得锌的生物利用率较低。肉类和肝脏的锌和铁含量高于未强化的植物性食物,并且已证明7月龄婴儿对其接受度良好。与发达国家和发展中国家的当前做法相反,应将肉类视为母乳喂养婴儿的早期补充食物,以提供必需的微量营养素。