Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, P.O. Box 14155-6117, Tehran, Iran.
Students' Scientific Research Center (SSRC), Tehran University of Medical Sciences (TUMS), Tehran, Iran.
Eur J Nutr. 2020 Aug;59(5):1815-1827. doi: 10.1007/s00394-020-02204-5. Epub 2020 Feb 24.
Despite previous investigations on the effects of zinc supplementation on blood pressure, inconsistent findings are available in this regard. Therefore, we conducted a systematic review and meta-analysis of randomized clinical trials on the effects of zinc supplementation on blood pressure (BP) in adults.
Relevant studies published up to September 2019 were searched through PubMed/Medline, Scopus, ISI Web of Science, and Google Scholar using suitable keywords. All randomized clinical trials (RCTs) that examined the effect of oral zinc supplementation on systolic blood pressure (SBP) or diastolic blood pressure (DBP) in adults were included.
Overall, nine trials were included in our study. Zinc supplementation significantly reduced SBP compared to the control [weighted mean differences (WMD) - 1.49 mmHg; 95% CI - 2.85 to - 0.13; P = 0.03]. However, zinc supplementation had no significant effects on DBP (WMD - 0.88 mmHg; 95% CI - 2.04 to 0.29; P = 0.14). Nonlinear analysis failed to indicate a significant influence of supplementation dosage or duration on both SBP and DBP. Sensitivity analysis showed that no individual study had a significant impact on our final results. In addition, we found no evidence for the presence of small-study effects among studies for both SBP and DBP.
We found a significant reduction in SBP following zinc supplementation. However, zinc supplementation had no significant effect on DBP. In addition, no nonlinear association was found between supplementation dosage and duration with changes in both SBP and DBP. Further RCTs using different dosages of zinc in various durations are required to confirm our conclusion.
尽管先前有研究探讨了补锌对血压的影响，但这方面的结果并不一致。因此，我们对补锌对成人血压（BP）影响的随机临床试验进行了系统评价和荟萃分析。
通过 PubMed/Medline、Scopus、ISI Web of Science 和 Google Scholar 搜索截至 2019 年 9 月发表的相关研究，使用合适的关键词。所有纳入的研究均为观察口服补锌对成人收缩压（SBP）或舒张压（DBP）影响的随机临床试验。
共有 9 项试验纳入本研究。与对照组相比，补锌显著降低 SBP [加权均数差（WMD）-1.49mmHg；95%置信区间（CI）-2.85 至-0.13；P=0.03]。然而，补锌对 DBP 无显著影响（WMD-0.88mmHg；95%CI-2.04 至 0.29；P=0.14）。非线性分析表明，补锌剂量或持续时间对 SBP 和 DBP 均无显著影响。敏感性分析显示，没有单个研究对我们的最终结果有显著影响。此外，我们未发现 SBP 和 DBP 研究中存在小样本研究效应的证据。
我们发现补锌后 SBP 显著降低，但补锌对 DBP 无显著影响。此外，补锌剂量和持续时间与 SBP 和 DBP 变化之间未发现非线性关联。需要进一步开展不同剂量补锌、不同持续时间的 RCT 以验证我们的结论。
