Cinnamon effect on blood pressure remains controversial. The present pilot study assessed cinnamon effect on blood pressure, and metabolic profile of stage 1 hypertension patients (S1HTN).
This double-blind placebo-controlled randomized trial was conducted between June and October 2019, in Mashhad, Iran. Study inclusion criteria comprised S1HTN diagnosis, based on 24-hour ambulatory blood pressure monitoring (ABPM). Subjects were randomly assigned to two groups: cinnamon group (capsule, 1500 mg/day, 90 days) and placebo group. On days 0 and 90, ABPM derived systolic and diastolic blood pressure (SBP and DBP, respectively), blood lipid profile, and fasting blood sugar (FBS) were recorded.
The two groups did not differ significantly regarding vascular risk factors, educational status, lipid profile and blood pressure at baseline, except for lower HDL-c in cinnamon group (p=0.03). On day 90, there was no significant difference between two study groups for lipid profile and blood pressure. A statistically significant decrease in mean 24-hr SBP and mean day SBP was observed in the cinnamon group, while mean night SBP and mean night DBP were decreased significantly in the placebo group after 90 days. A statistically significant decrease in mean change of day value of SBP was found in the cinnamon group, compared to the placebo. On day 90, FBS remained practically unchanged but a significant increase in HDL-c (5.8 unit; p=0.01) and a significant decrease in LDL-c levels (17.7 unit; p=0.009) were observed in the cinnamon group compared to placebo group.