Hibiscus sabdariffa L. drink improves postural stress-induced myocardial oxygen consumption changes in young adult men and women

Abstract

Aim: We hypothesized that Hibiscus sabdariffa drink would affect pressor and myocardial oxygen consumption (MVO 2 ) responses induced by postural stress in young healthy volunteers, and that the impact would be stronger in women than men. Materials and Methods: In a randomized, controlled, cross-over study, 25 young healthy male and 25 female subjects (18-27 years) drank nothing (control), water (500 ml; vehicle) or H. sabdariffa (1.4% w/v) 30 min before standing on three separate days of appointment. We measured supine and standing brachial blood pressure and heart rate (HR). MVO 2 was also estimated by the rate-pressure product (RPP). Results: Increases in systolic blood pressure (SBP) and RPP induced by standing when nothing or water was drunk was significantly larger (P < 0.05) than when H. sabdariffa drink was taken in both male and female subjects. However, H. sabdariffa drink had a stronger (P < 0.05) effect on SBP in women than in men, whereas the effect on RPP was stronger (P < 0.05) in men. Increases in diastolic blood pressure (DBP) and HR induced by standing when water was drunk were significantly larger than when H. sabdariffa drink was ingested in men. Conversely, increase in DBP induced by standing during water ingestion was not significantly attenuated by H. sabdariffa drink in women. Conclusion: The findings in the present study indicate H. sabdariffa drink impacts positively on the heart by reducing its demand for O 2 during postural stress, with a stronger effect in men relatively to women. This may be an important dietary intervention in preventing the development of cardiac dysfunctions among young individuals.