The beneficial effects of cinnamon among patients with metabolic diseases: A systematic review and dose-response meta-analysis of randomized-controlled trials
Emad Kutbi, Mohammad Hassan Sohouli, Somaye Fatahi, Abolfazl Lari, Farzad Shidfar, Maha Mari Aljhdali, Faisal Musaad Alhoshan, Saad Saif Elahi, Hashem Ameen Almusa, Ahmed Abu‐Zaid
Abstract
This systematic review and meta-analysis aims to summarize and conclude the clinical evidence regarding the use of cinnamon among patients with metabolic diseases. A comprehensive literature search without any limitation on language was conducted using the following bibliographical databases: ISI Web of Science, Embase, Scopus, PubMed, and Google Scholar. Search was conducted up to 23 January 2020. A total of 35 clinical trials were included for final analysis. Pooling of results showed a significant reducing effect of cinnamon on total cholesterol (TC) (weighted mean difference (WMD) = -11.67 mg/dL; P = 0.010), triglyceride (TG) (WMD = -16.27 mg/dL; P < 0.001), low density lipoprotein-cholesterol (LDL-C) (WMD = -6.36 mg/dL; P < 0.001), serum glucose (WMD = -11.39 mg/dL; P < 0.001), serum insulin (WMD = -1.27 μIU/mL; P = 0.028), and waist circumstance (WC) (WMD = -1.68 cm; P = 0.016). These lowering effects on TG, TC, LDL-C, and serum glucose levels were robust in studies that used cinnamon supplementation dose ≤1.5 g. Also, our findings of the present meta-analysis showed that cinnamon supplementation could have favorable effects on high density lipoprotein-cholesterol (HDL-C, WMD = 1.35; P = 0.038) as well as systolic (WMD = -3.95 mmHg; P = 0.018) and diastolic (WMD = -3.36; P = 0.001) blood pressure among patients with metabolic diseases. The present meta-analysis suggests that cinnamon might exert beneficial effects on various cardiometabolic risk factors among patients with metabolic diseases.