Lycopene Supplementation and Blood Pressure: Systematic review and meta-analyses of randomized trials

Abstract

Background & aims: Hypertension is a predisposing factor for cardiovascular disease (CVD). Results of previous clinical trials on the effects of lycopene supplementation on blood pressure are inconsistent. This systematic review and meta-analysis of randomized trials with parallel or cross-over design was conducted to summarize the effects of lycopene supplementation on blood pressure (BP). Methods: A systematic search was carried out in PubMed, SCOPUS, EMBASE and ISI Web of Science, without any restrictions on date and language publication to February 2020. Data were pooled using random-effects method and were expressed as weighted mean difference (WMD) and 95 confidence intervals (CI). Results: The elementary search consisted of 2564 records. Finally, 10 RCTs were included in the study. The pooled results of 10 studies with 16 effect size sizes including 688 participants (case=438 and control=250) showed that lycopene supplementation significantly decreased systolic blood pressure (SBP) (weighted mean differences (WMD): − 2.63 mmHg; 95 CI: − 5.17, − 0.09; P = 0.042). Greater effects on SBP were observed in subjects with a baseline SBP≥ 130 mmHg, at the lycopene dosages of ≥ 15 mg, duration≥ 8 weeks, and in hypertensive subjects. The changes observed in diastolic blood pressure (DBP) (WMD: −1.02 mmHg; 95 CI: −2.51, 0.46; P = 0.179) were not statistically significant. However, subgroup analysis showed that DBP decreased significantly in studies that enrolled hypertensive subjects or with elevated DBP (>80 mmHg). Lycopene supplementation reduced SBP in non-linear fashion based on dosage (P-nonlinearity = 0.04, Coef = −9.68). Conclusion: The present study demonstrates the beneficial effects of lycopene supplementation on BP levels. © 2021