Cinnamon use in type 2 diabetes: an updated systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 24019277 · doi:10.1370/afm.1517
What was done
Systematic review and meta-analysis of randomized controlled trials (RCTs) searched across MEDLINE, Embase, and CENTRAL through February 2012. Included trials evaluated cinnamon versus control in patients with type 2 diabetes and reported glycated hemoglobin (HbA1c), fasting plasma glucose, total cholesterol, LDL-C, HDL-C, or triglycerides. Weighted mean differences with 95% confidence intervals were calculated using random-effects models.
What was found
Ten RCTs (n = 543 patients) evaluated cinnamon doses from 120 mg/d to 6 g/d for 4 to 18 weeks. Cinnamon significantly reduced fasting plasma glucose (-24.59 mg/dL; 95% CI, -40.52 to -8.67), total cholesterol (-15.60 mg/dL; 95% CI, -29.76 to -1.44), LDL-C (-9.42 mg/dL; 95% CI, -17.21 to -1.63), and triglycerides (-29.59 mg/dL; 95% CI, -48.27 to -10.91), while increasing HDL-C (1.66 mg/dL; 95% CI, 1.09 to 2.24). No statistically significant effect was seen for HbA1c (-0.16%; 95% CI, -0.39% to 0.02%).
Why it matters
Cinnamon supplementation improves fasting glucose and lipid parameters in type 2 diabetes, but evidence does not demonstrate an effect on long-term glycemic control as measured by HbA1c.
Limits
High heterogeneity was present across all analyses except HDL-C (I² from 66.5% to 94.72%). Dosing varied fifty-fold (120 mg/d to 6 g/d) across short study durations (4 to 18 weeks), the cumulative sample size was modest (n = 543), and optimal therapeutic dose and duration remain unclear.
Cited by
- supports Scientific research shows that cinnamon has an impact on lowering or regulating blood sugar.