The effect of cinnamon supplementation on glycemic control in patients with type 2 diabetes or with polycystic ovary syndrome: an umbrella meta-analysis on interventional meta-analyses

Meysam Zarezadeh; Vali Musazadeh; Elaheh Foroumandi; Majid Keramati; Alireza Ostadrahimi; Rania A Mekary

doi:10.1186/s13098-023-01057-2

The effect of cinnamon supplementation on glycemic control in patients with type 2 diabetes or with polycystic ovary syndrome: an umbrella meta-analysis on interventional meta-analyses

Diabetol Metab Syndr. 2023 Jun 15;15(1):127. doi: 10.1186/s13098-023-01057-2.

Authors

Meysam Zarezadeh^#^{1

2}, Vali Musazadeh^#^{1

2}, Elaheh Foroumandi³, Majid Keramati^{1

2}, Alireza Ostadrahimi⁴, Rania A Mekary⁵

Affiliations

¹ Student Research Committee, Nutrition Research Center, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
² School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
³ Non- Communicable Diseases Research Center, Department of Nutrition and Biochemistry, Faculty Member of Medicine School, Sabzevar University of Medical Sciences, Sabzevar, Iran.
⁴ Nutrition Research Center, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran. ostadrahimi@tbzmed.ac.ir.
⁵ School of Pharmacy, MCPHS University, Boston, MA, 02115, USA. rania.mekary@mcphs.edu.

^# Contributed equally.

Abstract

Background: Several meta-analyses reported glycemic-lowering effects of cinnamon, while others reported conflicting findings. In the present study, we aimed to perform an umbrella meta-analysis of previous interventional meta-analyses on the effects of cinnamon on glycemic control in patients with type 2 diabetes (T2D) or with polycystic ovary syndrome (PCOS).

Methods: Relevant studies were searched in PubMed, Scopus, EMBASE, Web of Science, and Google Scholar up to June 2022. Meta-analyses of randomized clinical trials (RCTs) investigating the effects of cinnamon on glycemic indices including fasting plasma glucose (FPG), homeostatic model assessment for insulin resistance (HOMA-IR), insulin, and hemoglobin A1C (HbA1c) were included. Random-effects models were used to perform the umbrella meta-analysis and pool the weighted mean difference (WMD) or standardized mean difference (SMD) and their 95% confidence intervals (CI).

Results: Overall, 11 meta-analyses of RCTs were included. Cinnamon supplementation was effective in reducing serum FPG (WMD: -10.93 mg/dL; 95%CI: -16.22, -5.65; SMD: -0.86; 95%CI: -1.19, -0.52), insulin (WMD: -2.01 IU/mL; 95%CI: -3.96, -0.07; SMD: -0.61; 95%CI: -0.93, -0.30), HOMA-IR levels (WMD: -0.61; 95%CI: -0.91, -0.31; SMD: -0.78; 95%CI: -1.26, -0.30), and HbA1c (WMD: -0.10%; 95%CI: -0.17, -0.03).

Conclusion: Cinnamon can be used as an anti-diabetic agent and an add-on treatment to control glycemic indices among patients with T2D or PCOS.

Keywords: Cinnamon; Glycemic index; Polycystic ovary syndrome; Type 2 diabetes; Umbrella meta-analysis.

Publication types

Review