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The Effect of Hibiscus Sabdariffa L. Tea on Blood Pressure

This study has been completed.
Celestial Seasonings
Tufts Medical Center
Information provided by:
Tufts University Identifier:
First received: September 12, 2005
Last updated: December 2, 2009
Last verified: December 2009

September 12, 2005
December 2, 2009
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December 2007   (final data collection date for primary outcome measure)
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Complete list of historical versions of study NCT00175110 on Archive Site
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The Effect of Hibiscus Sabdariffa L. Tea on Blood Pressure
The Effect of Hibiscus Sabdariffa L. Tisane on Blood Pressure in Prehypertensive and Mildly Hypertensive Men and Women
The goal of this study is to find out whether the plant compounds present in Hibiscus sabdariffa, a plant commonly used in herbal tea blends and other beverages, will have a beneficial effect on blood pressure in people with mildly elevated blood pressure.
Not Provided
Phase 1
Phase 2
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
Behavioral: herbal therapy/botanical therapy (Hibiscus sabdariffa)
Not Provided
McKay DL, Chen CY, Saltzman E, Blumberg JB. Hibiscus sabdariffa L. tea (tisane) lowers blood pressure in prehypertensive and mildly hypertensive adults. J Nutr. 2010 Feb;140(2):298-303. doi: 10.3945/jn.109.115097.

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
December 2007
December 2007   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • Systolic blood pressure 120-150 mm Hg
  • Diastolic blood pressure 95 mm Hg or less
  • Body mass index (BMI) 18.5-34.9 kg/m2

Exclusion Criteria:

  • Smoking
  • Use of medications that influence blood pressure
  • Cardiovascular disease
  • Chronic kidney disease
  • Diabetes
  • Regular use of vitamin C supplements (min 500 mg/day) within prior 30 days
  • Regular strenuous aerobic activity greater than 30 min/day
  • Excessive intake of caffeine or alcohol
  • Pregnancy within last 6 months or during study period
  • Abnormal complete blood count (CBC), urinalysis or electrocardiogram (EKG)
30 Years to 70 Years   (Adult, Senior)
Contact information is only displayed when the study is recruiting subjects
United States
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Jeffrey B. Blumberg, Tufts University
Tufts University
  • Celestial Seasonings
  • Tufts Medical Center
Principal Investigator: Jeffrey B Blumberg, Ph.D. Tufts Medical Center
Tufts University
December 2009

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP