Effect of soluble fiber on blood pressure in adults: a systematic review and dose-response meta-analysis of randomized controlled trials

Abed Ghavami; Sara Banpouri; Rahele Ziaei; Sepide Talebi; Mahdi Vajdi; Elyas Nattagh-Eshtivani; Hanieh Barghchi; Hamed Mohammadi; Gholamreza Askari

doi:10.1186/s12937-023-00879-0

Effect of soluble fiber on blood pressure in adults: a systematic review and dose-response meta-analysis of randomized controlled trials

Nutr J. 2023 Oct 13;22(1):51. doi: 10.1186/s12937-023-00879-0.

Authors

Abed Ghavami¹, Sara Banpouri², Rahele Ziaei³, Sepide Talebi⁴, Mahdi Vajdi⁵, Elyas Nattagh-Eshtivani⁶, Hanieh Barghchi⁷, Hamed Mohammadi⁴, Gholamreza Askari⁸

Affiliations

¹ Department of Clinical Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran.
² Nutrition and Metabolic Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
³ Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran.
⁴ Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
⁵ Student Research Committee, Department of Community Nutrition, School of Nutrition and Food Science, Isfahan, Iran.
⁶ Department of Nutrition, Food Sciences and Clinical Biochemistry, School of Medicine, Social Determinants of Health Research Center, Gonabad University of Medical Science, Gonabad, Iran.
⁷ Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran.
⁸ Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran. askari@mui.ac.ir.

Abstract

Objectives: Pervious epidemiologic evidence indicates that soluble fiber is protective against hypertention: however, randomized controlled trials (RCTs) have presented varying results. In the present study, we aimed to conduct a systematic review and dose-response meta-analysis to summarize published RCTs which assess the effect of soluble fiber supplementation on systolic blood pressure (SBP) and diastolic blood pressure (DBP).

Methods: Scopus, PubMed, and ISI Web of Sciences were searched to identify relevant studies up to Aug 2022. We estimated the change in blood pressure for each 5 g/d increment in soluble fiber supplementation in each trial and then calculated the weighted mean difference (WMD) and 95%CI using a random-effects model. We estimated dose-dependent effects using a dose-response meta-analysis of differences in means. The risk of bias for study was assessed using the Cochrane tool. Publication bias was evaluated via funnel plot and Begg's test and Egger's test.

Results: Eighty-three eligible studies with total sample size of 5,985 participants were included in the meta-analysis. Soluble fiber supplementation significantly decreased SBP (WMD: -1.36 mmHg, 95% CI: -2.13 to -0.60, P < 0.001; I² = 47.1%, P < 0.001) and DBP (WMD: -0.72 mmHg, 95% CI: -1.26 to -0.18, P = 0.009; I² = 45.4%, P < 0.001). Each 5 g/d increment in soluble fiber supplementation had a significant reduction in SBP (WMD: -0.54 mmHg; 95%CI: -0.86, -0.22, P = 0.001; I² = 52.2, P_het < 0.001) and DBP (WMD: -0.28 mmHg; 95%CI: -0.49, -0.80, P = 0.007; I² = 43.1%, P_het < 0.001). The levels of SBP decreased proportionally with the increase in soluble fiber supplementation up to 20 g/d (MD_20g/d: -1.79 mmHg, 95%CI: -2.86, -0.71).

Conclusion: Current evidence indicated the beneficial effect of soluble fiber supplementation on blood pressure. Our findings suggest that soluble fiber supplementation could contribute to the management of hypertension and the reduction of cardiovascular disease risk.

Keywords: Blood pressure; Meta-analysis; Soluble fiber; Systematic review.

Publication types

Systematic Review
Meta-Analysis
Review

MeSH terms

Adult
Bias
Blood Pressure
Dietary Supplements*
Humans
Hypertension*
Randomized Controlled Trials as Topic