Research Centre for Prevention and Health, Glostrup University Hospital, Capital Region of Denmark, Glostrup, Denmark.
Br J Nutr. 2010 Apr;103(8):1195-204. doi: 10.1017/S0007114509992947. Epub 2009 Dec 8.
Danish legislation regarding food fortification has been very restrictive resulting in few fortified food items on the Danish market. Folate and vitamin B12 deficiency is thought to be common due to inadequate intakes but little is known about the actual prevalence of low serum folate and vitamin B12 in the general population. The aim of the present study was to evaluate the folate and vitamin B12 status of Danish adults and to investigate associations between vitamin status and distinct lifestyle and genetic factors. The study included a random sample of 6784 individuals aged 30-60 years. Information on lifestyle factors was obtained by questionnaires and blood samples were analysed for serum folate and vitamin B12 concentrations and several genetic polymorphisms. The overall prevalence of low serum folate ( < 6.8 nmol/l) was 31.4 %. Low serum folate was more common among men than women and the prevalence was lower with increasing age. Low serum folate was associated with smoking, low alcohol intake, high coffee intake, unhealthy diet, and the TT genotype of the methylenetetrahydrofolate reductase (MTHFR)-C677T polymorphism. The overall prevalence of low serum vitamin B12 ( < 148 pmol/l) was 4.7 %. Low serum vitamin B12 was significantly associated with female sex, high coffee intake, low folate status, and the TT genotype of the MTHFR-C677T polymorphism. In conclusion, low serum folate was present in almost a third of the adult population in the present study and was associated with several lifestyle factors whereas low serum concentrations of vitamin B12 were less common and only found to be associated with a few lifestyle factors.
丹麦的食品强化法规非常严格，导致市场上强化食品的种类很少。由于摄入不足，叶酸和维生素 B12 缺乏被认为很常见，但对于一般人群中血清叶酸和维生素 B12 的实际流行情况知之甚少。本研究旨在评估丹麦成年人的叶酸和维生素 B12 状况，并研究维生素状况与不同的生活方式和遗传因素之间的关系。该研究包括了一个随机抽取的 6784 名年龄在 30-60 岁的成年人样本。通过问卷获得生活方式因素的信息，采集血样分析血清叶酸和维生素 B12 浓度以及几种遗传多态性。血清叶酸水平低（<6.8nmol/l）的总患病率为 31.4%。血清叶酸水平男性高于女性，且随着年龄的增长而降低。低血清叶酸与吸烟、低酒精摄入、高咖啡摄入、不健康的饮食以及亚甲基四氢叶酸还原酶（MTHFR）-C677T 多态性的 TT 基因型有关。血清维生素 B12 水平低（<148pmol/l）的总患病率为 4.7%。低血清维生素 B12 与女性、高咖啡摄入、低叶酸状态以及 MTHFR-C677T 多态性的 TT 基因型显著相关。总之，在本研究中，近三分之一的成年人存在低血清叶酸，与多种生活方式因素有关，而低血清维生素 B12 则较为少见，仅与少数生活方式因素有关。
