title: Effects of Hibiscus sabdariffa L. on serum lipids: a systematic review and meta-analysis.
abstract: BACKGROUND
  Prevention of cardiovascular disease by modifying its major risk factors, including serum cholesterol levels, is an important strategy. Hibiscus sabdariffa L. has been promoted for reducing cholesterol levels, but its reported impact on cholesterol levels has been inconsistent. The study aimed to assess systematically the evidence and quality of current research on the effect of Hibiscus sabdariffa L. on blood lipids and its adverse effects.
  
  
  METHODS
  Electronic databases were searched up to June 2013 for relevant randomised controlled trials (RCTs). Journals and conference proceedings were also searched. The quality of the selected trials was assessed using the Cochrane Risk of Bias Assessment Tool. The efficacy results of similar studies were pooled if they used the same comparator. Outcomes examined were levels of total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol and triglycerides.
  
  
  RESULTS
  Six studies involving 474 subjects met our inclusion criteria. These studies varied in terms of the types of interventions, comparators used, and duration of trials. Overall, Hibiscus sabdariffa L. did not produce any significant effect on any of the outcomes examined, when compared with placebo, black tea or diet. With short-term use it is well tolerated.
  
  
  CONCLUSIONS
  The available evidence from RCTs does not support the efficacy of Hibiscus sabdariffa L. in lowering serum lipids. Further rigorously designed trials with larger sample sizes are warranted to confirm the effects of HS on serum lipids.
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia. Electronic address: zoriah@um.edu.my.
authors.forename: Zoriah
authors.initials: Z
authors.lastname: Aziz
authors.forename: Su Yuen
authors.initials: SY
authors.lastname: Wong
authors.forename: Nyuk Jet
authors.initials: NJ
authors.lastname: Chong
mesh_terms: D000818:Animals; D031584:Hibiscus; D006801:Humans; D006949:Hyperlipidemias / Q000188:drug therapy; D008055:Lipids / Q000097:blood*; D008517:Phytotherapy; D028321:Plant Preparations / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D008055:Lipids; D028321:Plant Preparations
keywords: Cholesterol; Hibiscus sabdariffa L.; Hyperlipidemia; Malvaceae; Roselle; Sour tea