Effect of conjugated linoleic acid on blood pressure: a meta-analysis of randomized, double-blind placebo-controlled trials

Lipids in Health and Disease

Li-Qiang Qin²  Tan Chen¹  Li Zhou³  Ling-Mei Zhou²  Hai-Peng Wang¹  Jing Yang³ 

[1] Department of Cardiology, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China;Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, 199 Renai Road, Dushu Lake Higher Education Town, Suzhou 215123, China;Department of Clinical Nutrition, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China

关键词: Meta-analysis;    Blood pressure;    Dairy products;    Conjugated linoleic acid;   

Others  :  1132945
DOI  :  10.1186/s12944-015-0010-9

 received in 2014-09-29, accepted in 2015-02-07,  发布年份 2015

【 摘 要 】

Background

Numerous studies on animals evidenced that conjugated linoleic acid (CLA) could decrease blood pressure (BP) in several rat models. However, such beneficial effect is not completely supported by studies on humans.

Methods

We searched the Pubmed, Cochrane Library, and the ClinicalTrials.gov databases for relevant randomized, double-blind placebo-controlled trials up to August 2014 to perform a meta-analysis. A random-effects model was used to calculate the combined treatment effects.

Results

Eight studies with nine trials, which involved 638 participants with CLA supplementation ranging from 2.0 g/day to 6.8 g/day, were included in this meta-analysis. Compared with placebo, the pooled estimate of change was −0.03 mm Hg (95% CI: −2.29, 2.24, P = 0.98) and 0.69 mm Hg (95% CI: −1.41, 2.80, P = 0.52) in systolic and diastolic BPs, respectively. No significant heterogeneity across studies for systolic BP; however, substantial heterogeneity for diastolic BP was identified. Publication bias was not found for both systolic and diastolic BPs.

Conclusion

The findings of this meta-analysis did not support the overall favorable effect of CLA supplementation on BP regulation.

【 授权许可】

   
2015 Yang et al.; licensee BioMed Central.

【 图 表 】

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