Mortensen Charlotte, Damsgaard Camilla T, Hauger Hanne, Ritz Christian, Lanham-New Susan A, Smith Taryn J, Hennessy Áine, Dowling Kirsten, Cashman Kevin D, Kiely Mairead, Mølgaard Christian
Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark;
Department of Nutrition and Midwifery, Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark.
Am J Clin Nutr. 2016 Nov;104(5):1310-1317. doi: 10.3945/ajcn.116.136697. Epub 2016 Oct 12.
Children in northern latitudes are at high risk of vitamin D deficiency during winter because of negligible dermal vitamin D production. However, to our knowledge, the dietary requirement for maintaining the nutritional adequacy of vitamin D in young children has not been investigated.
We aimed to establish the distribution of vitamin D intakes required to maintain winter serum 25-hydroxyvitamin D [25(OH)D] concentrations above the proposed cutoffs (25, 30, 40, and 50 nmol/L) in white Danish children aged 4-8 y living at 55°N.
In a double-blind, randomized, controlled trial 119 children (mean age: 6.7 y) were assigned to 0 (placebo), 10, or 20 μg vitamin D/d supplementation for 20 wk. We measured anthropometry, dietary vitamin D, and serum 25(OH)D with liquid chromatography-tandem mass spectrometry at baseline and endpoint.
The mean ± SD baseline serum 25(OH)D was 56.7 ± 12.3 nmol/L (range: 28.7-101.4 nmol/L). Serum 25(OH)D increased by a mean ± SE of 4.9 ± 1.3 and 17.7 ± 1.8 nmol/L in the groups receiving 10 and 20 μg vitamin D/d, respectively, and decreased by 24.1 ± 1.2 nmol/L in the placebo group (P < 0.001). A nonlinear model of serum 25(OH)D as a function of total vitamin D intake (diet and supplements) was fit to the data. The estimated vitamin D intakes required to maintain winter serum 25(OH)D >30 (avoiding deficiency) and >50 nmol/L (ensuring adequacy) in 97.5% of participants were 8.3 and 19.5 μg/d, respectively, and 4.4 μg/d was required to maintain serum 25(OH)D >40 nmol/L in 50% of participants.
Vitamin D intakes between 8 and 20 μg/d are required by white 4- to 8-y-olds during winter in northern latitudes to maintain serum 25(OH)D >30-50 nmol/L depending on chosen serum 25(OH)D threshold. This trial was registered at clinicaltrials.gov as NCT02145195.
由于冬季皮肤合成维生素D极少，北纬地区的儿童在冬季有维生素D缺乏的高风险。然而，据我们所知，尚未对维持幼儿维生素D营养充足的膳食需求量进行研究。
我们旨在确定居住在北纬55°的4-8岁丹麦白人儿童冬季血清25-羟基维生素D[25(OH)D]浓度维持在建议临界值（25、30、40和50 nmol/L）以上所需的维生素D摄入量分布。
在一项双盲、随机、对照试验中，119名儿童（平均年龄：6.7岁）被分配到每日补充0（安慰剂）、10或20μg维生素D，持续20周。我们在基线和终点时用液相色谱-串联质谱法测量人体测量指标、膳食维生素D和血清25(OH)D。
基线时血清25(OH)D的均值±标准差为56.7±12.3 nmol/L（范围：28.7-101.4 nmol/L）。接受每日10和20μg维生素D补充的组中，血清25(OH)D分别平均±标准误升高了4.9±1.3和17.7±1.8 nmol/L，而安慰剂组降低了24.1±1.2 nmol/L（P<0.001）。将血清25(OH)D作为总维生素D摄入量（膳食和补充剂）的函数的非线性模型与数据拟合。在97.5%的参与者中，维持冬季血清25(OH)D>30（避免缺乏）和>50 nmol/L（确保充足）所需的估计维生素D摄入量分别为每日8.3和每日19.5μg，而在50%的参与者中，维持血清25(OH)D>40 nmol/L需要每日4.4μg。
北纬地区4至8岁白人儿童冬季需要每日摄入8至20μg维生素D，以根据所选血清25(OH)D阈值维持血清25(OH)D>30-50 nmol/L。该试验在clinicaltrials.gov上注册为NCT02145195。
