Seyed Mohammad Mousavi1,2, Manije Darooghegi Mofrad1, Israel Júnior Borges do Nascimento3, Alireza Milajerdi1, Tahereh Mokhtari4, Ahmad Esmaillzadeh5,6,7. 1. Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, P.O. Box 14155-6117, Tehran, Iran. 2. Students' Scientific Research Center (SSRC), Tehran University of Medical Sciences (TUMS), Tehran, Iran. 3. University Hospital and School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. 4. Department of Nutrition and Integrative Physiology, College of Health, University of Utah, Salt Lake City, USA. 5. Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, P.O. Box 14155-6117, Tehran, Iran. a-esmaillzadeh@tums.ac.ir. 6. Obesity and Eating Habits Research Center, Endocrinology and Metabolism Molecular, Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran. a-esmaillzadeh@tums.ac.ir. 7. Food Security Research Center, Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran. a-esmaillzadeh@tums.ac.ir.
Abstract
PURPOSE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.
PURPOSE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.
Authors: Sara C Nevárez-López; Luis E Simental-Mendía; Fernando Guerrero-Romero; Jorge A Burciaga-Nava Journal: Int J Vitam Nutr Res Date: 2019-07-01 Impact factor: 1.784
Authors: Ashenafi H Betrie; James A Brock; Osama F Harraz; Ashley I Bush; Guo-Wei He; Mark T Nelson; James A Angus; Christine E Wright; Scott Ayton Journal: Nat Commun Date: 2021-06-01 Impact factor: 14.919