Cassia Cinnamon (Cinnamomum cassia) as a tool for helping with Cardiovascular / heart health

Context The global prevalence of type 2 diabetes mellitus (DM2) has been rising significantly over the years. Recent studies have shown beneficial effects of cinnamon on metabolic biomarkers. Objective The objective of this review was to assess the effect of cinnamon supplementation on metabolic biomarkers in patients with DM2. Data sources The Pubmed/MEDLINE, Cochrane CENTRAL, and Embase databases were searched up to November 10, 2022. Data extraction A systematic search was performed for randomized controlled trials (RCTs) evaluating the effect of cinnamon supplementation on metabolic biomarkers, in adults and the elderly with DM2, and comparing the data for a cinnamon intervention group with that for a placebo group or a control group. The main exclusion criteria were studies (1) with other types of diabetes (ie, gestational diabetes or type 1 diabetes), (2) without cinnamon consumption, (3) that did not evaluate metabolic biomarkers, or (4) in vitro and animal studies. Two researchers independently screened 924 records, evaluated full-text studies, extracted data, and appraised their quality. A third researcher was consulted to resolve any discrepancies. The data were pooled using random-effects models and expressed as the weighted mean difference (WMD) with 95% CI. Heterogeneity was assessed using Cochran's Q test and quantified using I2 statistics. Risk of bias was assessed using the Joanna Briggs Institute (JBI) instrument. Sensitivity analysis and the GRADE system were used to assess the robustness and certainty of the findings. Data analysis In total, 28 RCTs with a duration ranging from 30 to 120 days and a total enrollment of 3054 patients with DM2 were included. Participants consuming cinnamon showed a significant reduction in fasting blood glucose (FBG) (WMD: -15.26 mg/dL; 95% CI: -22.23 to -8.30; I2 = 88%), postprandial glucose (WMD: -39.22 mg/dL; 95% CI: -63.90 to -14.55; I2 = 100%), HbA1c (WMD: -0.56 mg/dL; 95% CI: -0.99 to -0.13; I2 = 94%), and HOMA-IR (WMD = -0.76, 95% CI: -1.13 to -0.39; I2 = 22%) compared with the control group. An intervention of cinnamon in capsule form reduced FBG (WMD:-18.43 mg/dL, 95% CI: -26.32 to -10.53; I2 = 89%), postprandial glucose (WMD: -44.83 mg/dL, 95% CI: -70.67 to -18.99; I2 = 100%), HbA1c (WMD: -0.56 mg/dL, 95% CI: -1.02 to -0.09; I2 = 94%), total cholesterol (WMD: -13.39 mg/dL; 95% CI: -24.71 to -2.07; I2 = 96%), LDL-C (WMD: -6.49 mg/dL, 95% CI: -12.69 to -0.29; I2 = 92%), and triglycerides (WND: -19.75 mg/dL; 95% CI, -33.71 to -5.80; I2 = 88%). Both doses (≤2 g/day and >2 g/day) reduced FBG and postprandial glucose. Only cinnamon doses of ≤2 g/day reduced HbA1c (WMD: -0.68 mg/dL, 95% CI: -1.16 to -0.1; I2 = 92%), HOMA-IR (WMD: -0.94 mg/dL; 95% CI: -1.21 to -0.67; I2 = 0%), and BMI (WMD: -1.18 kg/m2; 95% CI: -1.97 to -0.39; I2 = 0%). Conclusion The data suggest that cinnamon improves the glycemic and lipid profile and reduces the BMI, particularly in DM2 patients who receive cinnamon supplementation in capsule form and at a dose of ≤2 g/day. Systematic review registration PROSPERO registration no. CRD42022370332.

Control of diabetes is a constant challenge and natural remedies are being searched along with modern medicine. The effectiveness of cinnamon in managing it lacks consensus. Besides this, earlier trials had a variant in the type of product they used, quantity, duration, the form of molecules, etc. So, we aimed to measure the impact of cassia ground bark powder consumption, 1-2 gm/day for 90 days, in lowering plasma glucose and lipids among those with type 2 diabetes. The authors searched the PubMed, Medline, Embase, CINAHL, Clinical Key, Ovid, and Scopus databases and the Cochrane Central Register (last search December 30, 2020) with the MeSH terms and keywords of cinnamon, cassia cinnamon, Chinese cinnamon, and type 2 diabetes mellitus to conclude the effects of cassia cinnamon on diabetes based on the evidence of human clinical trials that reported at least one of the following: glycosylated hemoglobin (HbA1C), fasting blood glucose, total cholesterol, triglycerides, low-density lipoprotein (LDL), and high-density lipoprotein (HDL). Weighted mean differences were calculated by using the random-effect model of RevMan software (The Cochrane Collaboration, London, UK), and the pooled analysis found an insignificant reduction of the outcome variable (p>0.05).

Purpose Cinnamon has been studied in randomized controlled trials (RCTs) for its glycemic-lowering effects, but studies have been small and show conflicting results. A prior meta-analysis did not show significant results, but several RCTs have been published since then. We conducted an updated systematic review and meta-analysis of RCTs evaluating cinnamon's effect on glycemia and lipid levels. Methods MEDLINE, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched through February 2012. Included RCTs evaluated cinnamon compared with control in patients with type 2 diabetes and reported at least one of the following: glycated hemoglobin (A1c), fasting plasma glucose, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), or triglycerides. Weighted mean differences (with 95% confidence intervals) for endpoints were calculated using random-effects models. Results In a meta-analysis of 10 RCTs (n = 543 patients), cinnamon doses of 120 mg/d to 6 g/d for 4 to 18 weeks reduced levels of fasting plasma glucose (-24.59 mg/dL; 95% CI, -40.52 to -8.67 mg/dL), total cholesterol (-15.60 mg/dL; 95% CI, -29.76 to -1.44 mg/dL), LDL-C (-9.42 mg/dL; 95% CI, -17.21 to -1.63 mg/dL), and triglycerides (-29.59 mg/dL; 95% CI, -48.27 to -10.91 mg/dL). Cinnamon also increased levels of HDL-C (1.66 mg/dL; 95% CI, 1.09 to 2.24 mg/dL). No significant effect on hemoglobin A1c levels (-0.16%; 95%, CI -0.39% to 0.02%) was seen. High degrees of heterogeneity were present for all analyses except HDL-C (I(2) ranging from 66.5% to 94.72%). Conclusions The consumption of cinnamon is associated with a statistically significant decrease in levels of fasting plasma glucose, total cholesterol, LDL-C, and triglyceride levels, and an increase in HDL-C levels; however, no significant effect on hemoglobin A1c was found. The high degree of heterogeneity may limit the ability to apply these results to patient care, because the preferred dose and duration of therapy are unclear.