title: Association of tea consumption and the risk of thyroid cancer: a meta-analysis.
abstract: OBJECTIVE
  Epidemiological studies evaluating the association of tea consumption and the risk of thyroid cancer risk have produced inconsistent results. Thus, we conducted a meta-analysis to assess the relationship between tea consumption and thyroid cancer risk.
  
  
  METHODS
  Pertinent studies were identified by a search in PubMed and Web of Knowledge. The random effect model was used based to combine the results. Publication bias was estimated using Egger's regression asymmetry test.
  
  
  RESULTS
  Finally, 11 articles with 14 studies (2 cohort studies and 12 case-control studies) involving 2,955 thyroid cancer cases and 106,447 participants were included in this meta-analysis. The relative risk (95% confidence interval) of thyroid cancer for the highest versus the lowest category of tea consumption was 0.774 (95% CI = 0.619-0.967), and the associations were also significant in Europe and America, but not in the Asia. No publication bias was found.
  
  
  CONCLUSIONS
  Our analysis indicated that higher tea consumption may have a protective effect on thyroid cancer, especially in Europe and America.
authors.affiliation: Department of General Surgery, Zhangqiu People's Hospital Ji'nan, Shandong, 250200, P.R. China.
authors.forename: Sugang
authors.initials: S
authors.lastname: Ma
authors.affiliation: Department of Obstetrics and Gynecology, Zhangqiu People's Hospital Ji'nan, Shandong, 250200, P.R. China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of General Surgery, Zhangqiu People's Hospital Ji'nan, Shandong, 250200, P.R. China.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Bai
authors.affiliation: Department of General Surgery, Zhangqiu People's Hospital Ji'nan, Shandong, 250200, P.R. China.
authors.forename: Xipeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Orthopedics, Zhangqiu People's Hospital Ji'nan, Shandong, 250200, P.R. China.
authors.forename: Chuandong
authors.initials: C
authors.lastname: Li
keywords: Tea consumption; meta-analysis; thyroid cancer