Effect of cinnamon supplementation on blood pressure and anthropometric parameters in patients with type 2 diabetes: A systematic review and meta-analysis of clinical trials

Background and aims: The present systematic review and meta-analysis was conducted to investigate the effect of cinnamon supplementation on blood pressure and anthropometric indices in patients with type 2 diabetes. Methods: PubMed, Embase, Scopus, Web of Science and Cochrane Library were systematically searched to find relevant records up to 22 August 2019. Standard mean difference (SMD) and 95 confidence interval (CI) were used to evaluate the effect of cinnamon supplementation on the outcomes of this study. In the case of heterogeneity, fixed and random effect models were used. The obtained data were analyzed by Stata 13. After excluding irrelevant records, 9 eligible articles were included. Results: This meta-analysis found a significant reduction in systolic blood pressure (SBP) (SMD: �0.532, 95 CI: -1.032, �0.033, P = 0.037) and diastolic blood pressure (DBP) (SMD: �0.681, 95% CI: -1.297, �0.065, P = 0.030) of patients with type 2 diabetes following cinnamon supplementation. Based on the results of the present study, cinnamon supplementation had no significant effect on the body weight (BW) (SMD: �0.309, 95% CI: -0.793, 0.175, P = 0.211), body mass index (BMI) (SMD: �0.550, 95% CI: -1.244, 0.144, P = 0.120). and waist circumference (WC) (SMD: �0.235, 95% CI: -0.518, 0.047, P = 0.103). Conclusions: Cinnamon supplementation significantly decreased SBP and DBP of patients with type 2 diabetes. Although cinnamon intake caused changes in anthropometric parameters, the observed changes were not statistically significant. © 2020 Diabetes Indi