title: Tea consumption is not associated with reduced plasma folate concentration among Chinese pregnant women.
abstract: BACKGROUND
  The aim of this study was to evaluate the relationship between tea consumption and plasma folate concentration in populations with high and low prevalence of neural tube defects (NTDs) in China.
  
  
  METHODS
  Cross-sectional survey was conducted in three cities/counties in China, in which 1724 pregnant women during early second trimester were recruited and interviewed about tea consumption and folic acid use in 2011 to 2012. A total of 5-ml nonfasting blood sample was collected and plasma folate concentration was determined by microbiological assay.
  
  
  RESULTS
  Approximately 16.2% of the women reported that they had ever drank tea during and before the current pregnancy, women with higher educational level, and those who resided in urban were more likely to drink tea. Most of them prefer green tea (55.2%); 13.6% of women drank tea ">6 times/week," and 29.0% of them drank "less than once a week." The median of plasma folate concentration was 48.7 nmol/L in women who drank tea while it is 45.2 nmol/L in women who did not drink tea, with no statistical difference. The results showed there was no association between tea drinking and plasma folate concentration in Chinese pregnant women stratified by folic acid supplementation and other selected characteristics.
  
  
  CONCLUSIONS
  Low level of tea drinking is not associated with decreased plasma folate concentration in the Chinese populations with high and low prevalence of NTDs.
authors.affiliation: Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
authors.forename: Jufen
authors.initials: J
authors.lastname: Liu
authors.affiliation: Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Jin
authors.affiliation: Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
authors.forename: Yali
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
authors.forename: Le
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
authors.forename: Zhiwen
authors.initials: Z
authors.lastname: Li
authors.affiliation: Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
authors.forename: Rongwei
authors.initials: R
authors.lastname: Ye
authors.affiliation: Institute of Reproductive and Child Health/Ministry of Health Key Laboratory of Reproductive Health; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
authors.forename: Aiguo
authors.initials: A
authors.lastname: Ren
mesh_terms: D000328:Adult; D044466:Asian People; D003430:Cross-Sectional Studies; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000097:blood*; D006801:Humans; D009436:Neural Tube Defects / Q000097:blood; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000097:blood; D015995:Prevalence; D013662:Tea / Q000378:metabolism*
chemical_list: D013662:Tea; D005492:Folic Acid
keywords: folate; neural tube defects; residence; tea drinking