The effect of green coffee extract supplementation on blood pressure: A systematic review and meta‐analysis of randomized controlled trials

Abstract

Given the proliferation in studies investigating green coffee bean extract (GCBE) supplementation, the purpose of this study was to determine the efficacy and effectiveness of GCBE supplementation on indices of blood pressure. The literature search was performed in four databases, namely, PubMed/Medline, Scopus, the Cochrane Library, and Google Scholar, to identify clinical trials that examined the effects of green coffee supplements on systolic blood pressure (SBP) and diastolic blood pressure (DBP) up to February 2019. Mean change and standard deviation (SD) of the outcome measures were used to estimate the mean difference between the intervention group and the control group at follow‐up. Nine studies reported SBP and DBP as an outcome measure. Results revealed significant reduction in SBP (weighted mean difference: −3.093 mmHg, 95% confidence interval [CI]: −3.914, −2.273; I2 = 0.0%) and DBP (−2.170 mmHg, 95% CI: −2.749, −1.590; I2= 46.5%) after green coffee supplementation with low heterogeneity among the studies. In addition, in subgroup analysis, a significant reduction in SBP and DBP in studies with hypertensive patients, green coffee dosage <400 mg, and administered for 4 weeks was identified. The results of the current meta‐analysis study support the use of GCBE supplementation for the improvement of blood pressure indices, with subgroup analysis highlighting improvements in hypertensive patients.

The Effect of Dietary Polyphenols on Vascular Health and Hypertension: Current Evidence and Mechanisms of Action

“…While no intervention trials are available for regular coffee consumption and blood pressure, a meta-analysis of nine RCTs on green coffee extract supplementation showed a significant reduction in systolic (−3.09 mmHg, 95% CI: −3.91 to −2.27; I2 = 0.0%) and diastolic blood pressure (−2.17 mmHg, 95% CI: −2.74 to −1.59; I2 = 46.5%) with low heterogeneity among the studies [ 57 ]. In contrast, a quantitative summary of evidence on tea consumption has been conducted including 13 trials (1115 participants) on black tea (rich in hydroxybenzoic acids) and 24 trials (1697 participants) on green tea supplementation (rich in flavan-3-ols, such as epigallocatechin-gallate) showing a significant reduction in both systolic (−1.04 mmHg, 95% CI: −2.05 to −0.03, p = 0.04, and −1.17 mmHg, 95% CI: −2.18 to −0.16, p = 0.02, respectively) and diastolic blood pressure (−0.59 mmHg, 95% CI: −1.05 to −0.13, p = 0.01, and −1.24 mmHg, 95% CI:−2.07 to −0.40, p = 0.004, respectively), although with some evidence of heterogeneity between studies [ 58 , 59 ].…”

Insulin-Related Liver Pathways and the Therapeutic Effects of Aerobic Training, Green Coffee, and Chlorogenic Acid Supplementation in Prediabetic Mice

“…Green coffee (GC) is unroasted, increasing in use, is thought to have antioxidant and antiinflammatory properties, and has been propped as a treatment for certain diseases. Green coffee is rich in phytochemicals such as chlorogenic acid (CA) that is believed to be the main source of its beneficial properties [15][16][17][18].…”

Health Benefits of Green Coffee Beans

“…patients when green coffee in a dosage of 400 mg per day for 4 weeks was administered The results of that study support the use of GCBE supplementation for the improvement of blood pressure indices [63]. Several mechanisms by which CGAs or CGA metabolites cause hypotension have emerged:…”