Effects of strawberry intervention on cardiovascular risk factors: a meta-analysis of randomised controlled trials.

Abstract

We conducted a meta-analysis of randomised controlled trials (RCT) to examine the effects of strawberry interventions on cardiovascular risk factors. We searched multiple databases including PubMed, Web of Science and Scopus to identify eligible studies published before 19 May 2019. The endpoints were blood pressure, total cholesterol (TC), HDL-cholesterol, LDL-cholesterol, TAG, fasting blood glucose, endothelial function and inflammatory factors. Pooled analyses were performed using random- or fixed-effects models according to a heterogeneity test. We also conducted sub-group analyses by baseline endpoint levels. We included eleven RCT in this meta-analysis (six for blood pressure, seven for lipid profile, seven for fasting blood glucose and six for C-reactive protein (CRP)). Overall, the strawberry interventions significantly reduced CRP levels by 0·63 (95 % CI -1·04, -0·22) mg/l but did not affect blood pressure, lipid profile or fasting blood glucose in the main analyses. Our analysis stratified by baseline endpoint levels showed the strawberry interventions significantly reduced TC among people with baseline levels >5 mmol/l (-0·52 (95 % CI -0·88, -0·15) mmol/l) and reduced LDL-cholesterol among people with baseline levels >3 mmol/l (-0·31 (95 % CI -0·60, -0·02) mmol/l). There was little evidence of heterogeneity in the analysis and no evidence of publication bias. In summary, strawberry interventions significantly reduced CRP levels and may improve TC and LDL-cholesterol in individuals with high baseline levels.