The effect of garlic on vascular function: A systematic review of randomized clinical trials

Abstract

Backgrounds and aims: Atherosclerosis and its associated cardiovascular disease (CVD) represent a major global health problem worldwide and vascular dysfunction is important in its pathogenesis. Clinical trials investigating the effect of garlic on vascular function measured by several non-invasive methods and their results are inconsistent. This study aimed to summarize the current evidence regarding the effectiveness of garlic as one of the world's most ancient medicines on measures of vascular reactivity and/or stiffness in adults.

Methods: All published RCTs in English were systematically searched on PubMed, Scopus and Google Scholar search engines up to Oct 2019. The exposure and outcome variable of interest were garlic and vascular function measurements. Ten trials which met inclusion criteria were included in this study.

Results: A total of 45 studies were found through search databases. After excluding duplicates, the 25 remaining studies were screened by title and abstract which 15 of them excluded. Finally, ten trials were included in this review study, which were published between 2004 and 2018.

Conclusions: Findings were inconsistent. However, garlic has the potential to improve vascular function, particularly in subjects with cardiovascular risk factors. Additional human studies on garlic and its constituents should consider the population and the specific type of garlic preparation.

Keywords: Allium sativum; Atherosclerosis; CVD; Endothelial function; Garlic; Vascular function.