The Effect of Anthocyanin-Rich Foods or Extracts on Vascular Function in Adults: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

Anthocyanins are of interest due to their anti-oxidative and vasodilatory properties. Earlier reviews have shown that berries and other anthocyanin rich foods or extracts can improve vascular health, however the effect of anthocyanins on vascular function has not yet been reviewed. To address this gap in the literature, we conducted a systematic review and meta-analysis of randomised-controlled trials examining anthocyanin-rich foods or extracts on measures of vascular reactivity and/or stiffness in adults. Data from 24 studies were pooled as standardized mean difference (SMD) with 95% confidence intervals (CI). Anthocyanin consumption significantly improved flow-mediated dilation (FMD) following acute (SMD: 3.92%, 95% CI: 1.47, 6.38, p = 0.002; I(2) = 91.8%) and chronic supplementation (SMD: 0.84%, 95% CI: 0.55, 1.12, p = 0.000; I(2) = 62.5%). Pulse wave velocity was improved following acute supplementation only (SMD: −1.27 m/s, 95% CI: −1.96, −0.58, p = 0.000; I(2) = 17.8%). These results support the findings of previous reviews that anthocyanin rich foods or extracts may indeed improve vascular health, particularly with respect to vascular reactivity measured by FMD. More research is required to determine the optimal dosage, and the long-term effects of consumption.