Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
Office of Dietary Supplements, National Institutes of Health, 6100 Executive Blvd, 3B01, Bethesda, MD 20892, USA.
Nutrients. 2017 Dec 6;9(12):1327. doi: 10.3390/nu9121327.
Iron is particularly important in pregnancy and infancy to meet the high demands for hematopoiesis, growth and development. Much attention has been given to conditions of iron deficiency (ID) and iron deficient anemia (IDA) because of the high global prevalence estimated in these vulnerable life stages. Emerging and preliminary evidence demonstrates, however, a U-shaped risk at both low and high iron status for birth and infant adverse health outcomes including growth, preterm birth, gestational diabetes, gastrointestinal health, and neurodegenerative diseases during aging. Such evidence raises questions about the effects of high iron intakes through supplementation or food fortification during pregnancy and infancy in iron-replete individuals. This review examines the emerging as well as the current understanding of iron needs and homeostasis during pregnancy and infancy, uncertainties in ascertaining iron status in these populations, and issues surrounding U-shaped risk curves in iron-replete pregnant women and infants. Implications for research and policy are discussed relative to screening and supplementation in these vulnerable populations, especially in developed countries in which the majority of these populations are likely iron-replete.
铁在妊娠和婴儿期尤为重要，以满足造血、生长和发育的高需求。由于在这些脆弱的生命阶段估计全球流行率很高，因此人们非常关注缺铁（ID）和缺铁性贫血（IDA）的情况。然而，新出现的初步证据表明，在低铁和高铁状态下，出生和婴儿不良健康结果（包括生长、早产、妊娠期糖尿病、胃肠道健康和衰老期间的神经退行性疾病）存在 U 形风险。这种证据引发了对通过补充或食物强化在铁充足的个体中摄入高铁的影响的质疑。本综述检查了妊娠和婴儿期铁需求和体内平衡的新出现和当前理解，在这些人群中确定铁状态的不确定性，以及铁充足的孕妇和婴儿 U 形风险曲线的问题。讨论了与这些脆弱人群的筛查和补充相关的研究和政策的影响，特别是在大多数人群可能铁充足的发达国家。
