Analysis of the Efficacy of Cinnamon for Patients with Diabetes Mellitus Type II Based on Traditional Persian Medicine Syndrome Differentiation: A Randomized Controlled Trial

Background: Conflicting results have been obtained from the studies on the hypoglycemic effect of cinnamon in patients with diabetes mellitus type II (T2DM). Objectives: This research aimed at assessing the effect of applying the syndrome differentiation model based on traditional Persian medicine (TPM) to identify the patients who benefit more from cinnamon supplementation. Methods: This study was a randomized, triple-blind, placebo-controlled trial based on a parallel design. One hundred and forty eligible patients referring to the Diabetes Clinic of Yazd University of Medical Sciences, whowere diagnosedwith T2DM,were randomly divided into the cinnamon and placebo groups. Then, 500-mg capsules of cinnamon bark powder or placebo were administered to them twice a day for three months. All the participants completed a standard questionnaire for syndrome diagnosis in traditional Persian medicine (TPM). Fasting plasma glucose (FPG), glycated hemoglobin (HbA1C), fasting insulin (FI), and insulin resistance (IR), calorie intake, and physical activity were measured before and after the interventions. The glycemic outcomes were analyzed according to the TPM syndrome. Results: There was no statistically significant difference between the patients’ demographic and clinical features in the two groups. Glycemic indices were improved in patients receiving cinnamon supplementation compared to placebo group (-13.1 ± 1.7, -1.7 ± 1.9, P < 0.001 for change in FPG and -0.27 ± 0.039 vs. 0.001 ± 0.019, P < 0.001 for change in HbA1C respectively). All the outcomes were more improved in the patients with wet syndrome compared to dry ones, which was compatible with Persian syndrome differentiation (P < 0.05). Conclusions: Diabetic patients with wet syndrome based on TPM benefit more form cinnamon supplementation.