http://naturalmedicinejournal.com/artic ... rticle=215
A randomized, controlled, double-blind clinical comparison study was conducted on H. sabdariffa extract vs lisinopril (control) on patients with stage I or II hypertension.38 A dried, powdered hibiscus extract was delivered in 250 mg of water, containing a total of 250 mg anthocyanins for 4 weeks, and the control group received 10 mg/day of lisinopril. Results showed that the Hibiscus extract decreased blood pressure from 146/98 mmHg to 130/86 mmHg (P<0.05) Blood pressure reductions were lower than with lisinopril. Based on the study data, the authors concluded that the hibiscus extract did have a significant antihypertensive action through at least 2 mechanisms of action: diuretic effects (likely as an aldosterone antagonist) and ACE inhibitory effects. The study authors also noted that the diuretic activity did not alter plasma potassium levels and did not have mineralocorticoid effects.
Should be interesting!