title: Garlic for hypertension: A systematic review and meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  In the past decade, garlic has become one of the most popular complementary therapies for blood pressure (BP) control used by hypertensive patients. Numerous clinical studies have focused on the BP-lowering effect of garlic, but results have been inconsistent. Overall, there is a dearth of information available to guide the clinical community on the efficacy of garlic in hypertensive patients.
  
  
  OBJECTIVE
  To systematically review the medical literature to investigate the current evidence of garlic for the treatment of hypertension.
  
  
  METHODS
  PubMed, the Cochrane Library and EMBASE were searched for appropriate articles from their respective inceptions until August 2014. Randomized, placebo-controlled trials comparing garlic vs. a placebo in patients with hypertension were considered. Papers were independently reviewed by two reviewers and were analyzed using Cochrane software Revman 5.2.
  
  
  RESULTS
  A total of seven randomized, placebo-controlled trials were identified. Compared with the placebo, this meta-analysis revealed a significant lowering effect of garlic on both systolic BP (WMD: -6.71 mmHg; 95% CI: -12.44 to -0.99; P = 0.02) and diastolic BP (WMD: -4.79 mmHg; 95% CI: -6.60 to -2.99; P < 0.00001). No serious adverse events were reported in any of the trials.
  
  
  CONCLUSIONS
  The present review suggests that garlic is an effective and safe approach for hypertension. However, more rigorously designed randomized controlled trials focusing on primary endpoints with long-term follow-up are still warranted before garlic can be recommended to treat hypertensive patients.
authors.affiliation: Department of Cardiology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China. Electronic address: xiongxingjiangtcm@163.com.
authors.forename: X J
authors.initials: XJ
authors.lastname: Xiong
authors.affiliation: Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: P Q
authors.initials: PQ
authors.lastname: Wang
authors.affiliation: Department of Biological Science and Technology, School of Life Sciences, Tsinghua University, Beijing, China.
authors.forename: S J
authors.initials: SJ
authors.lastname: Li
authors.affiliation: Bio-organic and Natural Products Laboratory, McLean Hospital, Harvard Medical School, Belmont, MA, USA.
authors.forename: X K
authors.initials: XK
authors.lastname: Li
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada.
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Zhang
authors.affiliation: Department of Cardiology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: J
authors.initials: J
authors.lastname: Wang
mesh_terms: D000959:Antihypertensive Agents / Q000494:pharmacology*; D005737:Garlic; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D016032:Randomized Controlled Trials as Topic
chemical_list: D000959:Antihypertensive Agents
keywords: Blood pressure; Garlic; Hypertension; Randomized controlled trial; Systematic review