Effects of Hydroxyhydroquinone-reduced Coffee in Patients with Essential Hypertension

Abstract

Recent animal and human studies suggest that chlorogenic acids, which are the main component of the class of polyphenols in coffee, reduce blood pressure, and that hydroxyhydroquinone (HHQ), produced by roasting green coffee beans, inhibits the antihypertensive effect of chlorogenic acids in brewed coffee. To examine the effects of 4 weeks of daily ingestion of HHQ-reduced coffee in patients with essential hypertension undergoing treatment with antihypertensive drugs. Patients being treated for essential hypertension with antihypertensive drugs participated in a randomized, double-blind, crossover controlled trial. After a 2-week run-in phase, participants consumed two cans of either HHQ-reduced coffee or Control coffee daily for 4 weeks. After a 2-week washout period, subjects were crossed over to the other treatment. Blood pressure and pulse rate were measured once a week. Blood biochemistry and hematology analysis was performed before and after the test beverage ingestion periods. A4 -week ingestion period of HHQ-reduced coffee did not significantly change systolic blood pressure (SBP) or diastolic blood pressure (DBP) compared to the Control coffee. There were no significant changes in pulse rate and body weight during the test beverage ingestion periods in either group, and no clinically relevant problems were reported. These findings suggest that 4 weeks of daily ingestion of HHQ-reduced coffee does not reduce or enhance the efficacy of antihypertensive drugs in treated essential hypertensive patients.