January 28, 2020
Jemima Jennyl B. Baquiran, DMD
Cinnamon (Cinnamon casia) is a medicinal plant that has insulin-potentiating compounds. These doubly linked type-A polyphenol compounds have been shown to alleviate the signs and symptoms of diabetes and cardiovascular disease related to insulin resistance.
As cinnamon influences the insulin system, it was hypothesized that cinnamon improves glycemic control through improved insulin sensitivity. It was also noted to decrease blood pressure in patients with diabetes type 2.
In 2010, cinnamon was reported to have blood glucose-lowering and blood pressure lowering potential; it may also be able to ease the signs and symptoms of diabetes and cardiovascular diseases. In this technical article summary, the short-term administration of cinnamon is evaluated on BP regulation in patients with prediabetes and Type 2 diabetes.
Insulin resistance occurring in cardiovascular, muscle, and liver tissue, contributes to the development of endothelial dysfunction and hypertension. As such, hypertension is common in patients with Type 2 diabetes, affecting 60% of the population.
The 2013 study by Akilen et al. aims to systematically review the short-term effect of cinnamon intake on blood pressure regulation in prediabetic and type 2 diabetic patients through a meta-analysis of randomized, placebo-controlled clinical trials.
Three original articles of randomized clinical trials were selected out of 93 studies. Overall, 139 participants were included in the meta-analysis. Two studies showed significant reduction in SBP and one study showed marginally significant reduction in SBP with cinnamon. Two studies did not show significant reduction in DBP though one study showed significant reduction in DBP. Collectively, there is a significant decrease on SBP and DBP by 5.39mm Hg and 2.6 mmHg respectively.
For patients with well controlled BP levels (SBP <130 mmHg and DBP of< 80 mmHg), the effect of cinnamon on SBP or DBP may be at minimum. That is why in the study conducted by Wainstein et. al, it did not demonstrate a significant reduction in diastolic blood pressure when cinnamon was given at 1.2 grams per day for 12 weeks. It is most likely that the therapeutic dose of cinnamon may depend on the patients’ base line BP rather than the dose-dependent effect.
Nevertheless, Ziegenfuss et al reported a 3.8% SBP reduction in participants with a mean baseline of 133mm Hg when cinnamon extract is ingested at 500mg, daily for 12 weeks. This demonstrates that higher cinnamon dose can bring a significant reduction in SBP.
Ziegenfuss et al and Akilen et al showed significant reduction in SBP or DBP followed by FPG or HbA1c reduction. This would suggest that the ability to lower BP by cinnamon is closely related to its blood glucose- lowering potential.
Cinnamon has been reported to improve the antioxidant status of patients with metabolic syndrome. Foods with antioxidant effect repress oxidative stress. Oxidative stress plays a major role in the progression of diabetes and cardiovascular disease. The antioxidant effect could be linked with BP regulation.
It has been verified that short term cinnamon consumption can indeed have a reduction of SBP and DBP. However, with limited evidence, it is still unjustifiable to recommend cinnamon to solely control blood pressure.