Cinnamon supplementation positively affects obesity: A systematic review and dose-response meta-analysis of randomized controlled trials

Background & aims: Data about the effects of cinnamon supplementation on obesity measures are conflicting. This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to summarize the effects of cinnamon intake on body weight (BW), Body Mass Index (BMI), Waist Circumference (WC), and fat mass (FM) in adults.

Methods: Online electronic search engines including PubMed, SCOPUS, Cochrane Library, and Google Scholar were searched to find pertinent articles until September 2018. Data were pooled using the random-effects method and were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). The non-linear association was assessed using fractional polynomial modeling.

Results: Out of 679 records, 12 trials that enrolled 786 subjects were included. The pooled results showed that cinnamon administration significantly decreased BW (WMD: -1.02 kg, 95% CI: -1.66 to -0.38, P = 0.002), BMI (WMD: -0.51 kg/m², 95% CI: -0.74, -0.28, P < 0.001), WC (WMD: -2.40 cm, 95% CI: -4.48, -0.33, P = 0.02), and FM (WMD: -1.02%, 95% CI: -1.80, -0.24, P = 0.01). Greater effects on BW were observed in subjects aged <50 years old and those with a baseline BMI of ≥30 kg/m². The cinnamon administrations significantly reduced FM at the dosages of ≥2 g/d, when administered for ≥12 weeks. Cinnamon administration resulted in BW and WC reduction in non-linear fashion (P = 0.04).

Conclusions: Cinnamon supplementation significantly affects obesity measures. It could be recommended as a weight-reducing supplement in obesity management.