title: Coffee consumption and risk of gastric cancer: an updated meta-analysis.
abstract: OBJECTIVE
  Coffee is one of the most widely consumed beverages worldwide, and many studies have investigated the association between coffee consumption and gastric cancer. However, the results are inconsistent. We conducted a systematic analysis of relevant population studies to derive a more precise estimation.
  
  
  METHODS
  Cochrane library, PubMed and Embase databases were searched to identify studies that met predetermined inclusion criterion through July 2014. All epidemiologic studies regarding coffee consumption and gastric cancer risk were selected, and relative risks (RRs) with 95% confidence intervals (CIs) were calculated.
  
  
  RESULTS
  Twenty two studies (9 cohort and 13 case-control studies) involving 7,631 cases and 1,019,693 controls were included. The summary RR of gastric cancer was 0.94 (95% CI: 0.80-1.10) for the highest category of coffee consumption compared with the lowest category, and 0.93 (95% CI: 0.88-0.99) for coffee drinkers compared with nondrinkers. We stratified the population by coffee consumption. The pooled RR for the population with <1 cup/day, 1-2 cups/day and 3-4 cups/day coffee consumption compared with nondrinkers were 0.95 (95% CI: 0.84-1.08), 0.92 (95% CI: 0.82-1.03) and 0.88 (95% CI: 0.76-1.02), respectively, indicating that an increase in coffee consumption was associated with a decreased risk of gastric cancer. Furthermore, we stratified the studies by design, sex, population and time. A significant association between coffee intake and decreased gastric cancer risk was shown in case-control studies (RR=0.85, 95% CI: 0.77-0.95) and among the studies published over the last ten years (RR=0.88, 95% CI: 0.77-1.00).
  
  
  CONCLUSIONS
  Our meta-analysis suggested that coffee consumption might be associated with a decreased risk of gastric cancer.
authors.affiliation: Department of Laboratory Medicine, Chongqing Key Laboratory of Pediatrics, Ministry of Education Key Laboratory of Child Development and Disorders, the Children's Hospital of Chongqing Medical University, Lab medicine of Yubei Maternity and Children Care Hospital, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Department of Laboratory Medicine, Chongqing Key Laboratory of Pediatrics, Ministry of Education Key Laboratory of Child Development and Disorders, the Children's Hospital of Chongqing Medical University, Lab medicine of Yubei Maternity and Children Care Hospital, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing, China.
authors.forename: Shifeng
authors.initials: S
authors.lastname: Huang
authors.affiliation: Department II of Orthopaedics, Stem Cell Biology and Therapy Laboratory, Chongqing Key Laboratory of Pediatrics, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation base of Child development and Critical Disorders, the Children's Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Tongchuan
authors.initials: T
authors.lastname: He
authors.affiliation: Department II of Orthopaedics, Stem Cell Biology and Therapy Laboratory, Chongqing Key Laboratory of Pediatrics, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation base of Child development and Critical Disorders, the Children's Hospital of Chongqing Medical University, Chongqing, China. Email: yuxisu@163.com.
authors.forename: Yuxi
authors.initials: Y
authors.lastname: Su
mesh_terms: D016022:Case-Control Studies; D003069:Coffee / Q000009:adverse effects; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D012306:Risk; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000517:prevention & control*
chemical_list: D003069:Coffee