Cinnamon was associated with reductions in systolic and diastolic blood pressure of 5.39 and 2.6 mmHg, report scientists in Nutrition.
Numerous studies have reported that cinnamon and the compounds it contains may improve parameters associated with diabetes. The meta-analysis, performed by scientists from the University of Toronto (Canada), the University of West London (UK), and London South Bank University (UK) is said to be the first to evaluate the effects of cinnamon on blood pressure in diabetics.
“Although cinnamon shows hopeful effects on blood pressure-lowering potential, it would be premature to recommend cinnamon for blood pressure control, and this may raise expectations in terms of potential utility of cinnamon supplementation in blood pressure regulation, which seem unjustified given the limited evidence to date,” wrote the researchers, led by Rajadurai Akilen, PhD.
“Given the limited number of studies available, undoubtedly, a long-term, adequately powered, clinical RCT involving a larger number of patients is needed to appraise the clinical potential of cinnamon on blood pressure control among patients with pre-diabetes and [type-2 diabetes].”
Out of a possible 93 identified studies, Dr Akilen and his co-workers limited their meta-analysis to only three randomized clinical trials, two of which included diabetics while the third was with pre-diabetics.
The doses of cinnamon used in the studies ranged from 500 mg to 2.4 grams per day, and all the studies lasted for 12 weeks.
Crunching the numbers yielded the result that cinnamon intake was associated with significant decreases in both systolic and diastolic blood pressure.
Commenting on the potential mechanisms of action, Dr Akilen and his co-workers said that a recent review had “confirmed that cinnamon and components of cinnamon have been shown to have beneficial effects on virtually all of the factors associated with metabolic syndrome, including insulin sensitivity, glucose, lipids, antioxidants, inflammation, blood pressure, and body weight.”
“In summary, this meta-analysis of three RCTs indicates that the consumption of cinnamon (short term) is associated with notable reduction of systolic and diastolic blood pressure in patients with prediabetes and [type-2 diabetes],” they wrote.
“However, the precise relationship between blood pressure regulation and the effect of cinnamon in humans remains unclear and to be established in future studies.”
Published online ahead of print, doi: 10.1016/j.nut.2013.03.007
“Effect of short-term administration of cinnamon on blood pressure in patients with prediabetes and type 2 diabetes”
Authors: R. Akilen, Z. Pimlott, A. Tsiami, N. Robinson