From the Institute of Food and Health, University College Dublin, Belfield Dublin, Republic of Ireland (SMH, MJG, APN, and BAM); the Northern Ireland Centre for Food and Health, University of Ulster, Coleraine, Northern Ireland (HM, JJS, and MW); the School of Clinical Medicine, Trinity College, Dublin, Republic of Ireland (AMM and JMS); and the School of Food and Nutritional Sciences, University College Cork, Cork, Republic of Ireland (AF and JW).
Am J Clin Nutr. 2015 Jun;101(6):1163-72. doi: 10.3945/ajcn.115.107151. Epub 2015 Apr 15.
Ireland has traditionally operated a liberal policy of voluntary fortification, but little is known about how this practice, along with supplement use, affects population intakes and status of folate and vitamin B-12.
The aim was to examine the relative impact of voluntary fortification and supplement use on dietary intakes and biomarker status of folate and vitamin B-12 in Irish adults.
Folic acid and vitamin B-12 from fortified foods and supplements were estimated by using brand information for participants from the cross-sectional National Adult Nutrition Survey 2008-2010. Dietary and biomarker values were compared between 6 mutually exclusive consumption groups formed on the basis of folic acid intake.
The consumption of folic acid through fortified foods at low, medium, and high levels of exposure [median (IQR) intakes of 22 (13, 32), 69 (56, 84), and 180 (137, 248) μg/d, respectively]; from supplements [203 (150, 400) μg/d]; or from both sources [287 (220, 438) μg/d] was associated with significantly higher folate intakes and status compared with nonconsumption of folic acid (18% of the population). Median (IQR) red blood cell (RBC) folate increased significantly from 699 (538, 934) nmol/L in nonconsumers to 1040 (83, 1390) nmol/L in consumers with a high intake of fortified foods (P < 0.001), with further nonsignificant increases in supplement users. Supplement use but not fortification was associated with significantly higher serum vitamin B-12 concentrations relative to nonconsumers (P < 0.001). Two-thirds of young women had suboptimal RBC folate for protection against neural tube defects (NTDs); among nonconsumers of folic acid, only 16% attained optimal RBC folate.
The consumption of voluntarily fortified foods and/or supplement use was associated with significantly higher dietary intakes and biomarker status of folate in Irish adults. Of concern, the majority of young women remain suboptimally protected against NTDs.
爱尔兰一直实行自愿强化政策，但是对于这种做法，以及补充剂的使用如何影响叶酸和维生素 B-12 的人群摄入量和状况，人们知之甚少。
本研究旨在调查自愿强化和补充剂使用对爱尔兰成年人饮食摄入和叶酸及维生素 B-12 生物标志物状况的相对影响。
利用 2008-2010 年全国成人营养调查中参与者的品牌信息，估算强化食品和补充剂中叶酸酸和维生素 B-12 的含量。根据叶酸摄入量将 6 个相互排斥的消费组形成基于叶酸摄入量的消费组，比较各组的饮食和生物标志物值。
低、中、高暴露水平（暴露中位数（IQR）分别为 22（13，32）、69（56，84）和 180（137，248）μg/d）、补充剂（203（150，400）μg/d）或两者均摄入（287（220，438）μg/d）与非叶酸消费相比，叶酸摄入量和状态显著升高（人群的 18%）。与非叶酸消费者（699（538，934）nmol/L）相比，高摄入量强化食品消费者的红细胞（RBC）叶酸中位数（IQR）显著升高（1040（83，1390）nmol/L）（P<0.001），补充剂使用者的 RBC 叶酸进一步显著增加。与非叶酸消费者相比，补充剂的使用而不是强化与血清维生素 B-12 浓度显著升高（P<0.001）。三分之二的年轻女性的 RBC 叶酸水平不足以预防神经管缺陷（NTD）；在非叶酸消费者中，只有 16%的人达到了最佳 RBC 叶酸水平。
自愿强化食品的消费和/或补充剂的使用与爱尔兰成年人饮食中叶酸的摄入量和生物标志物状况显著升高有关。值得关注的是，大多数年轻女性仍然无法充分预防 NTD。
