Effects of grape seed extract on dyslipidaemia: a systematic review and dose–response meta-analysis of randomised controlled trials

Abstract

Data on the effect of grape seed extract (GSE) on lipid profiles are inconclusive. We undertook a systematic review and meta-analysis of randomised controlled clinical trials on the effect of GSE on serum lipid profiles. The online databases of PubMed, ISI Web of Science, Scopus, ProQuest, Science Direct and Embase were searched for relevant publications until March 2019, using MeSH and non-MeSH keywords. Study selection, data extraction and quality assessment were completed independently by two investigators. Meta-regression and subgroup analyses were performed to identify the source of heterogeneity. Assessment of study quality was conducted using the Jadad scale. Eleven randomised clinical trials involving 536 participants were included in the present meta-analysis. Combining effect sizes from earlier studies, we found that GSE supplementation significantly decreased serum levels of LDL-cholesterol (−0·17 mmol/l; 95 % CI −0·34, −0·01) and TAG (−0·11 mmol/l; 95 % CI −0·18, −0·05). Although no overall significant effect of GSE supplementation on circulating total- and HDL-cholesterol levels was observed, there were significant reductions in these lipids in studies with <10 weeks of intervention and those that had administered the dosages of <300 mg/d of GSE. In conclusion, GSE supplementation seems to favourably affect serum levels of LDL and TAG concentrations, but it did not affect total- and HDL-cholesterol concentrations.

Efficacy of Bilberry and Grape Seed Extract Supplement Interventions to Improve Glucose and Cholesterol Metabolism and Blood Pressure in Different Populations—A Systematic Review of the Literature

“…One meta-analysis found that interventions with bilberry extract improved LDL and HDL cholesterol levels in subjects at risk of cardiovascular disease, in subjects with metabolic syndrome and in those with hypercholesterolemia [ 13 ], whereas a systematic review concluded that interventions with grape polyphenols did not significantly affect glycemia, insulin sensitivity, cholesterol levels or blood pressure [ 14 ]. This was in contrast to a recent meta-analysis suggesting that intervention with grape seed extract decreased LDL cholesterol and triglycerides across studies [ 15 ], and another meta-analysis suggesting that grape seed extracts decreased systolic and diastolic blood pressure, especially in subjects with metabolic syndrome and pre-hypertension [ 16 ]. Significant differences in applied inclusion and exclusion criteria between reviews in relation to study designs, study populations and outcome parameters led to inclusion of different studies, and therefore to different conclusions.…”

“…A systematic review by Woerdeman et al [ 14 ] concluded that interventions with grape polyphenols did not significantly affect glycemia, insulin sensitivity, cholesterol levels or blood pressure, arguably due to differences in study quality, study populations and study durations. A recent meta-analysis, including meta-regression and subgroup analysis to identify sources of heterogeneity in previous reviews, concluded that intervention with grape seed extract decreased LDL cholesterol and triglycerides across studies, and LDL and total cholesterol in studies with less than 10 weeks of intervention, and in those studies providing <300 mg/d of grape seed extract [ 15 ]. The meta-analysis by Zhang et al [ 16 ] concluded that grape seed extracts decreased systolic and diastolic blood pressure, with effects being significantly more pronounced in subjects with metabolic syndrome and in pre-hypertensive individuals.…”

The effect of grape seed extract supplementation on oxidative stress and inflammation: A systematic review and meta‐analysis of controlled trials

“…48 Furthermore, it is possible that the ability of GSE to lower lipid levels causes an additive reduction in the concentrations of lipid peroxidation biomarkers. 56 Importantly, the results of our subgroup analysis show that low-dose and long-term supplementation with GSE may be more effective in the reduction of lipid peroxidation biomarkers than high-dose and short-term supplementation with GSE. Such a result may be obtained by the possible pro-oxidant effects of GSE at doses ≥1000 mg/d.…”

Systematic Review and Meta-analysis of Randomised Controlled Trials Testing the Effects of Proanthocyanidins Supplementation on Lipid Profile

“…Grape seed PCs are the major polyphenols component of grape seeds, which have strong anti-in ammatory and antioxidant activity 54 . A previous meta-analysis by Anjom-Shoae has indicated that grape seed extract (GSE) supplementation had a signi cant effect on LDL-C and TG, but do not affect TC or HDL-C 55 . However, our results are inconsistent with the ndings mentioned above.…”