The effect of cinnamon supplementation on cardiovascular risk factors in adults: a GRADE assessed systematic review, dose-response and meta-analysis of randomized controlled trials

Abstract

Background Numerous clinical studies have suggested that cinnamon supplementation may be effective for cardiovascular disease risk factors, but the findings are controversial. This comprehensive systematic review and meta-analysis aimed to assess the impact of cinnamon supplementation on cardiovascular disease risk factors. Methods Relevant studies were identified through electronic searches of databases, including Web of Science, PubMed, Central, Scopus, and Embase, up to July 2024. Results Forty-nine studies were included. Cinnamon supplementation significantly reduced WC (SMD = - 0.40; 95% (CI): - 0.73, - 0.06), DBP (SMD = - 1.04; 95% CI: - 1.54, - 0.55), SBP (SMD = - 0.85; 95% CI: - 1.54, - 0.16), fasting glucose (SMD = - 1.28; 95% CI: - 1.65, - 0.90), fasting insulin (SMD = - 0.26; 95% CI: - 0.50, - 0.02), HbA1c (SMD = - 0.71; 95% CI: - 1.02, - 0.40), HOMA-IR (SMD = - 0.54; 95% CI: - 0.82, - 0.26), postprandial blood glucose (SMD = - 2.28; 95% CI: - 3.48, - 1.08), CRP (SMD = - 0.78; 95% CI: - 1.28, - 0.27), LDL-C (SMD = - 0.71; 95% CI: - 1.02, - 0.40), total cholesterol (TC) (SMD = - 1.15; 95% CI: - 1.55, - 0.75), triglycerides (TG) (SMD = - 0.91; 95% CI: - 1.25, - 0.56), and MDA (SMD = - 0.76; 95% CI: - 1.07, - 0.45). Additionally, cinnamon supplementation significantly elevated HDL-C levels (SMD = 0.56; 95% CI: 0.23, 0.89). Conclusion Cinnamon supplementation demonstrated significant benefits in improving cardiovascular risk factors. These findings suggest its potential as an adjunct therapy for improving cardiovascular disease risk factors.