Antihypertensive potential of combined extracts of olive leaf, green coffee bean and beetroot: a randomized, double-blind, placebo-controlled crossover trial

Wong, Rachel H. X. and Garg, Manohar L. and Wood, Lisa G. and Howe, Peter R. C. (2014) Antihypertensive potential of combined extracts of olive leaf, green coffee bean and beetroot: a randomized, double-blind, placebo-controlled crossover trial. Nutrients, 6 (11). pp. 4881-4894.

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Extracts of olive leaf, green coffee bean and beetroot may deliver cardiovascular benefits. This study sought to evaluate the effects of regularly consuming a combination of these extracts on blood pressure (BP), arterial compliance, blood lipids, blood glucose and insulin sensitivity. A double-blind randomised placebo-controlled crossover trial was conducted in adults with untreated high normal or borderline elevated BP. They were randomised to take an active supplement, comprising 500 mg olive leaf extract, 100 mg green coffee bean extract and 150 mg beet powder, or a matching placebo twice daily for six weeks, followed by the alternate supplement for a further six weeks. Assessments of 24-h ambulatory BP (ABP), clinic BP arterial compliance (pulse-wave analysis), blood lipids, blood glucose and insulin were obtained at baseline and at the end of each treatment phase. Baseline clinic BP in 37 overweight middle-aged men and women who completed the trial averaged 145/84 mmHg. There was no significant effect of treatment on ABP or any other outcome measure. The failure to confirm prior evidence of the antihypertensive benefits of these extracts emphasises the importance of placebo control and the value of ABP monitoring. Further dose-response evaluation of olive leaf, green coffee bean or beetroot extracts is required to confirm or refute the purported benefits.

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Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Faculty/School / Institute/Centre: No Faculty
Faculty/School / Institute/Centre: No Faculty
Date Deposited: 01 Jun 2017 06:14
Last Modified: 02 Nov 2017 02:02
Uncontrolled Keywords: Ambulatory blood pressure; Chlorogenic acid; Cholesterol; Hypertension; Insulin sensitivity; Olive leaf extract; Adolescent; Antihypertensive Agents; Beta vulgaris; Blood Glucose; Blood Pressure; Cholesterol, HDL; Cholesterol, LDL; Coffee; Cross-Over Studies; Dietary Supplements; Double-Blind Method; Female; Healthy Volunteers; Heart Rate; Humans; Insulin; Male; Middle Aged; Olea; Plant Extracts; Plant Leaves; Plant Roots; Treatment Outcome; Triglycerides; Young Adult; Cardiovascular Diseases and Cardiovascular Surgery; Drug Literature Index; Adverse Reactions Titles
Fields of Research (2008): 11 Medical and Health Sciences > 1111 Nutrition and Dietetics > 111199 Nutrition and Dietetics not elsewhere classified
Fields of Research (2020): 32 BIOMEDICAL AND CLINICAL SCIENCES > 3210 Nutrition and dietetics > 321099 Nutrition and dietetics not elsewhere classified
Socio-Economic Objectives (2008): E Expanding Knowledge > 97 Expanding Knowledge > 970111 Expanding Knowledge in the Medical and Health Sciences
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