Human Nutrition Laboratory, Institute of Food Nutrition and Health, ETH Zurich, Zurich, Switzerland.
Iodine Global Network, Ottawa, Ontario, Canada.
J Nutr. 2018 Apr 1;148(4):587-598. doi: 10.1093/jn/nxy015.
Dietary iodine requirements are high during pregnancy, lactation, and infancy, making women and infants vulnerable to iodine deficiency. Universal salt iodization (USI) has been remarkably successful for preventing iodine deficiency in the general population, but it is uncertain if USI provides adequate iodine intakes during the first 1000 d.
We set out to assess if USI provides sufficient dietary iodine to meet the iodine requirements and achieve adequate iodine nutrition in all vulnerable population groups.
We conducted an international, cross-sectional, multicenter study in 3 study sites with mandatory USI legislation. We enrolled 5860 participants from 6 population groups (school-age children, nonpregnant nonlactating women of reproductive age, pregnant women, lactating women, 0-6-mo-old infants, and 7-24-mo-old infants) and assessed iodine status [urinary iodine concentration (UIC)] and thyroid function in Linfen, China (n = 2408), Tuguegarao, the Philippines (n = 2512), and Zagreb, Croatia (n = 940). We analyzed the iodine concentration in household salt, breast milk, drinking water, and cow's milk.
The salt iodine concentration was low (<15 mg/kg) in 2.7%, 33.6%, and 3.1%, adequate (15-40 mg/kg) in 96.3%, 48.4%, and 96.4%, and high (>40 mg/kg) in 1.0%, 18.0%, and 0.5% of household salt samples in Linfen (n = 402), Tuguegarao (n = 1003), and Zagreb (n = 195), respectively. The median UIC showed adequate iodine nutrition in all population groups, except for excessive iodine intake in school-age children in the Philippines and borderline low intake in pregnant women in Croatia.
Salt iodization at ∼25 mg/kg that covers a high proportion of the total amount of salt consumed supplies sufficient dietary iodine to ensure adequate iodine nutrition in all population groups, although intakes may be borderline low during pregnancy. Large variations in salt iodine concentrations increase the risk for both low and high iodine intakes. Strict monitoring of the national salt iodization program is therefore essential for optimal iodine nutrition. This trial was registered at clinicaltrials.gov as NCT02196337.
妊娠、哺乳期和婴儿期对碘的需求量很高，这使得妇女和婴儿容易受到碘缺乏的影响。在一般人群中，全民食盐碘化（USI）在预防碘缺乏方面取得了显著成功，但目前尚不确定 USI 是否能在最初的 1000 天内提供足够的碘摄入量。
我们旨在评估 USI 是否能为所有易感人群提供足够的膳食碘，以满足碘的需求并实现足够的碘营养。
我们在中国临汾（n=2408）、菲律宾图格加劳（n=2512）和克罗地亚萨格勒布（n=940）的 3 个研究点进行了一项国际、横断面、多中心研究，这些研究点都有强制性的 USI 立法。我们招募了来自 6 个人群组（学龄儿童、育龄非孕非哺乳期妇女、孕妇、哺乳期妇女、0-6 月龄婴儿和 7-24 月龄婴儿）的 5860 名参与者，并评估了碘状况[尿碘浓度（UIC）]和甲状腺功能。我们分析了家庭盐、母乳、饮用水和牛奶中的碘浓度。
家庭盐样本中盐碘浓度<15 mg/kg 的比例分别为 2.7%、33.6%和 3.1%，15-40 mg/kg 的比例分别为 96.3%、48.4%和 96.4%，>40 mg/kg 的比例分别为 1.0%、18.0%和 0.5%，分别来自中国临汾（n=402）、菲律宾图格加劳（n=1003）和克罗地亚萨格勒布（n=195）的 402、1003 和 195 个盐样本。除了菲律宾学龄儿童碘摄入过多和克罗地亚孕妇碘摄入临界低值外，所有人群组的中位数 UIC 均显示出足够的碘营养。
覆盖大部分食盐摄入量的 25 mg/kg 盐碘化水平提供了足够的膳食碘，以确保所有人群组的足够碘营养，尽管在怀孕期间摄入量可能处于临界低值。盐碘浓度的巨大差异增加了低碘和高碘摄入的风险。因此，严格监测国家盐碘化计划对于优化碘营养至关重要。本试验在 clinicaltrials.gov 注册，编号为 NCT02196337。
