Randomized, double-blind clinical trial evaluating the impact of freeze-dried garlic extract capsules on blood pressure, lipid profile, and nitric oxide levels in individuals at risk for hypertension

Elham Rahmatinia; Bardia Amidi; Narges Naderi; Saeedeh Ahmadipour; Hasan Ahmadvand; Mohammad-Taha Pahlevan-Fallahy; Vajihe Ghorbanzadeh; Afshin Nazari

doi:10.1515/hmbci-2024-0019

Article

Randomized, double-blind clinical trial evaluating the impact of freeze-dried garlic extract capsules on blood pressure, lipid profile, and nitric oxide levels in individuals at risk for hypertension

Elham Rahmatinia , Bardia Amidi , Narges Naderi , Saeedeh Ahmadipour , Hasan Ahmadvand , Mohammad-Taha Pahlevan-Fallahy , Vajihe Ghorbanzadeh and Afshin Nazari

Published/Copyright: July 15, 2024

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From the journal Hormone Molecular Biology and Clinical Investigation Volume 45 Issue 4

Abstract

Objectives

Hypertension, substantially heightens the risk of cardiovascular disease. This study aims to evaluate the effectiveness of freeze-dried garlic extract in blood pressure and lipid profiles in prehypertensive individuals.

Methods

Participants (age of 30–70 years) were allocated to intervention (n=47) or control (n=49) groups. The intervention group received two capsules of freeze-dried garlic extract daily for eight weeks, while the control group received identical placebo capsules. Primary outcomes, SBP, DBP, PP, MAP, TC, TG, LDL and HDL levels, serum NO levels, were assessed at baseline, four weeks, and eight weeks.

Results

At the end of study, results showed significant changes in the values of SBP, DBP, and MAP except for PP. In comparison to those who received the placebo, a significant drop in SBP, DBP (p<0.001), and MAP (p<0.001) was observed in the intervention group. Also, there were significant changes in TG, LDL, TC, and HDL levels in the interventional group. A noticeable decline was reported in TG (p<0.001), LDL (p<0.001), and TC (p<0.001), while HDL levels increased (p<0.001) in the intervention group compared to those receiving the placebo. Following garlic supplementation, a significant increase in blood NO levels was reported in the intervention group (p<0.001).

Conclusions

The study showed that garlic supplementation was effective in lowering blood pressure, improving lipid profile, and increasing nitric oxide levels in prehypertensive participants. These results indicate that garlic could be a valuable complementary therapy for managing prehypertension.

Keywords: blood pressure; lipid profile; freeze-dried garlic extract capsules; nitric oxide

Corresponding authors: Vajihe Ghorbanzadeh and Afshin Nazari, Cardiovascular Research Center, Shahid Rahimi Hospital, Lorestan University of Medical Sciences, Khorramabad, Iran, E-mail: vghorbanzadeh@gmail.com (V. Ghorbanzadeh), nazary257@yahoo.com (A. Nazari)

Research ethics: IR.LUMS.REC.1400.102.
Informed consent: All participant signing a written informed consent form to participate in the study.
Author contributions: E.R., B.A. and N.N. writing original draft, S.A. and H.A. data collection, M.T.P.F. and V.Gh visualization, validation, A.N. project administration, supervision. All these authors have substantial contributions to the final manuscript and approved this submission.
Competing interests: There is no conflict of interest.
Research funding: There is no funding research.
Data availability: The data that support the findings of this study are available from the first author, upon reasonable request.

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Received: 2024-04-29

Accepted: 2024-07-02

Published Online: 2024-07-15

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Articles in the same Issue

https://doi.org/10.1515/hmbci-2024-0019

Keywords for this article

blood pressure; lipid profile; freeze-dried garlic extract capsules; nitric oxide