The effect of cinnamon tea on postprandial blood glucose levels.
(2016) The effect of cinnamon tea on postprandial blood glucose levels., no. 31.
Aim: Elevated postprandial blood glucose levels have been associated with cardiovascular death as well as contributing to high glycated hemoglobin levels in diabetic individuals. Previous studies suggest that cinnamon lowers postprandial blood glucose levels due to the action of polyphenols on various mechanisms. The aim of this study was to determine if the consumption of 95ml cinnamon tea significantly reduces postprandial blood glucose levels in non-diabetic individuals following an oral glucose tolerance test. Methods: Cinnamon tea was prepared by boiling 6g cinnamon sticks in 100ml water for 30minutes. In this randomised controlled trial, 18 healthy subjects were randomly allocated to the control group (n=9) or the intervention group (n=9). After fasting for 10 hours, subjects consumed an oral glucose tolerance test followed by either 95ml cinnamon tea (intervention group) or 95ml water (control group). Blood glucose levels of the two groups were measured and compared at baseline, 30 minutes, 60 minutes and 90 minutes, as well as area under the curve being calculated and compared for between both groups. Laboratory analysis was carried out to measure the antioxidant ability of the cinnamon tea using the ferric reducing antioxidant power method and the total phenolic content was determined using the Folin and Ciocalteau method. Results: There was no significant difference between the blood glucose levels of the control and intervention group at baseline, t30, t60 or t90 (P>0.05). The area under the curve was not significantly lower with the consumption of cinnamon tea (P>0.05). Laboratory analysis revealed that the cinnamon tea had a high total phenolic content (1.2 ± 0.1g/L of gallic acid equivalent) and strong antioxidant power (7.2 ±0.6 mM Fe2+). Conclusion: This study concluded that the intake of cinnamon tea following an oral glucose tolerance test does not significantly reduce post prandial glucose levels. However, it remains inconclusive whether or not the consumption of cinnamon in other forms lowers post prandial glucose levels due to substantial evidence from existing studies. Keywords: Cinnamon tea, Postprandial blood glucose, Polyphenols, Diabetes, Glycemic control