Department of Midwifery and Women's Health, Division of Health Sciences and Nursing, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Biosci Trends. 2010 Oct;4(5):225-30.
Folate is a vital nutrient during pregnancy for the prevention of neural tube defects, intrauterine fetal growth restriction and preeclampsia. Circulating folate levels might be negatively affected by ()-epigallocatechin gallate, which is a tea catechin found in green tea and oolong tea. The aim of this study was to determine whether consumption of green tea or oolong tea was associated with circulating folate levels among pregnant women in Japan. Two hundred and fifty-four healthy women with a singleton pregnancy (age: 30.4 ± 4.7, gestational age: 27.5 ± 9.6 weeks) were recruited from a prenatal clinic in metropolitan Tokyo, Japan. The serum folate levels were measured. Nutrient intake was assessed using a self-administered diet history questionnaire. Information on lifestyle variables was obtained from the questionnaire. The high consumption of green tea or oolong tea was defined as consumption more than 57.3 mL per 1,000 kcal, which is the 75th percentile of participants. The serum folate levels of the participants with high consumption of green tea or oolong tea was significantly lower than those of others (p = 0.027). A multiple regression analysis revealed the high consumption of green tea or oolong tea to be associated with a low serum folate level during pregnancy, after adjusting for confounding variables including dietary folate intake and use of folic acid supplements or multivitamins (β = -0.131, p = 0.016). The association between folate and the consumption of green tea or oolong tea may be useful to clarify the mechanism which links adverse perinatal outcomes and tea consumption.
叶酸是孕妇怀孕期间预防神经管缺陷、宫内胎儿生长受限和子痫前期的重要营养素。循环叶酸水平可能会受到（-）-表没食子儿茶素没食子酸酯的负面影响，（-）-表没食子儿茶素没食子酸酯是绿茶和乌龙茶中发现的一种茶儿茶素。本研究旨在确定日本孕妇饮用绿茶或乌龙茶是否与循环叶酸水平有关。从日本东京大都会的一家产前诊所招募了 254 名健康的单胎妊娠妇女（年龄：30.4±4.7 岁，妊娠周数：27.5±9.6 周）。测量血清叶酸水平。使用自我管理的饮食史问卷评估营养素摄入量。从问卷中获取生活方式变量的信息。高绿茶或乌龙茶的摄入量定义为每 1000 千卡摄入超过 57.3 毫升，这是参与者的第 75 百分位数。高绿茶或乌龙茶摄入量组的血清叶酸水平明显低于其他组（p=0.027）。多元回归分析显示，在调整了膳食叶酸摄入量以及叶酸补充剂或多种维生素的使用等混杂因素后，高绿茶或乌龙茶的摄入量与孕期血清叶酸水平较低有关（β=-0.131，p=0.016）。叶酸与绿茶或乌龙茶摄入量之间的关联可能有助于阐明与不良围产期结局和茶类消费相关的机制。
