title: Effect of green tea consumption on blood pressure: a meta-analysis of 13 randomized controlled trials.
abstract: The studies investigating the effects of green tea on blood pressure (BP) have generated inconsistent results. The aim of this study is to quantitatively evaluate the effects of green tea on BP control. PubMed, Embase, and the Cochrane Library (updated to March 2014) were searched for randomized controlled trials evaluating the effects of green tea on BP. Pooled effect of green tea consumption on BP was evaluated using fixed-effects or random-effects model. Thirteen trials comprising a total of 1,367 subjects were included in the current meta-analysis. The overall outcome of the meta-analysis suggested that green tea consumption significantly decrease systolic blood pressure (SBP) level by -1.98 mmHg (95% CI: -2.94, -1.01 mmHg; P < 0.001). Compared with the control group, green tea also showed a significant lowering effect on diastolic blood pressure (DBP) in treatment group (-1.92 mmHg; 95% CI: -3.17, -0.68 mmHg; P = 0.002). Subgroup analyses further suggested that the positive effect of green tea polyphenols on BP was only showed in studies using a low-dose green tea polyphenol, with the long-term intervention duration or ruling out the confounding effects of caffeine. The meta-analysis suggested that green tea consumption had a favorable effect on decrease of BP.
authors.affiliation: 1] Department of Epidemiology and Health Statistics, Institute of Public Health, Chengdu Medical College, Chengdu 610083, Sichuan, China [2] Research Center for Nutrition and Food Safety, Institute of Military Preventive Medicine, Third Military Medical University, Chongqing Key Laboratory of Nutrition and Food Safety, Chongqing Medical Nutrition Research Center, Chongqing 400038, China [3].
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Peng
authors.affiliation: 1] Research Center for Nutrition and Food Safety, Institute of Military Preventive Medicine, Third Military Medical University, Chongqing Key Laboratory of Nutrition and Food Safety, Chongqing Medical Nutrition Research Center, Chongqing 400038, China [2].
authors.forename: Rui
authors.initials: R
authors.lastname: Zhou
authors.affiliation: Research Center for Nutrition and Food Safety, Institute of Military Preventive Medicine, Third Military Medical University, Chongqing Key Laboratory of Nutrition and Food Safety, Chongqing Medical Nutrition Research Center, Chongqing 400038, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Epidemiology and Health Statistics, Institute of Public Health, Chengdu Medical College, Chengdu 610083, Sichuan, China.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Yu
authors.affiliation: Department of Epidemiology and Health Statistics, Institute of Public Health, Chengdu Medical College, Chengdu 610083, Sichuan, China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Yang
authors.affiliation: Research Center for Nutrition and Food Safety, Institute of Military Preventive Medicine, Third Military Medical University, Chongqing Key Laboratory of Nutrition and Food Safety, Chongqing Medical Nutrition Research Center, Chongqing 400038, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Liu
authors.affiliation: Research Center for Nutrition and Food Safety, Institute of Military Preventive Medicine, Third Military Medical University, Chongqing Key Laboratory of Nutrition and Food Safety, Chongqing Medical Nutrition Research Center, Chongqing 400038, China.
authors.forename: Mantian
authors.initials: M
authors.lastname: Mi
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects*; D002110:Caffeine / Q000494:pharmacology; D006801:Humans; D010936:Plant Extracts / Q000494:pharmacology*; D059808:Polyphenols / Q000494:pharmacology*; D016032:Randomized Controlled Trials as Topic; D013662:Tea / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D059808:Polyphenols; D013662:Tea; D002110:Caffeine