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The Effect of Grape Seed Extract on Estrogen Levels of Postmenopausal Women

This study has been completed.
Information provided by (Responsible Party):
Dietlind Wahner-Roedler, Mayo Clinic Identifier:
First received: November 30, 2007
Last updated: January 4, 2012
Last verified: January 2012
The role of estrogens in the pathogenesis of breast cancer has been well documented. This has led to the development of "Anti-Estrogens" (selective estrogens receptor modulators and Aromatase Inhibitors), used for treatment and prevention of breast cancer. These agents, however, have significant side effects, which are not acceptable to many healthy high-risk women. There is preliminary evidence that grape seed extract acts as "natural" aromatase inhibitor (1). This study has the potential to quantify the effectiveness of a natural substance that mimics the action of pharmaceutical aromatase inhibitors.

Condition Intervention
Breast Cancer
Dietary Supplement: Grape Seed Extract

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: The Effect of Grape Seed Extract on Estrogen Levels of Postmenopausal Women: A Pilot Study

Resource links provided by NLM:

Further study details as provided by Mayo Clinic:

Primary Outcome Measures:
  • To document that grape seed extract taken orally will decrease plasma estrogen levels (estrone (E1), estradiol (E2), and E1-conjugates) and increase precursor androgen levels (testosterone and androstenedione) in healthy postmenopausal women. [ Time Frame: 12 weeks ]

Secondary Outcome Measures:
  • To determine the most effective, well tolerated dose of grape seed extract resulting in a decrease in plasma estrogen levels (E1, E2, E1-conjugates) and increase in precursor androgens (testosterone and androstenedione). [ Time Frame: 12 weeks ]

Enrollment: 39
Study Start Date: February 2008
Study Completion Date: September 2011
Primary Completion Date: September 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Grape Seed Extract # 1
200 mg [1 pill]
Dietary Supplement: Grape Seed Extract
200 mg dose daily for 12 weeks.
Other Name: ActiVin®
Active Comparator: Grape Seed Extract # 2
200 mg [2 pills]
Dietary Supplement: Grape Seed Extract
400 mg dose daily for 12 weeks.
Other Name: ActiVin®
Active Comparator: Grape Seed Extract # 3
200 mg [3 pills]
Dietary Supplement: Grape Seed Extract
600 mg dose daily for 12 weeks.
Other Name: ActiVin®
Active Comparator: Grape Seed Extract # 4
200 mg [4 pills]
Dietary Supplement: Grape Seed Extract
800 mg dose daily for 12 weeks.
Other Name: ActiVin®

Detailed Description:
Early detection of breast cancer with screening mammography and the use of more effective medical therapies have led to a decrease in breast cancer mortality. However, breast cancer is still the second leading cause of cancer death in women (2). Therefore, the future lies in not only early detection but prevention of breast cancer. Currently available chemopreventive agents are associated with potentially serious side effects and can be quite costly, especially when taken for extended periods of time. Therefore, they are usually targeted only to women at high risk of disease. Identification of an inexpensive, efficacious preventive therapy with few or no side effects would represent a major advance in reducing the morbidity and mortality due to breast cancer. One exciting possibility is grape seed extract. Grapes and grape seeds contain procyanidins, a highly active subclass of flavonoids with actions similar to pharmaceutical aromatase inhibitors (AIs). These procyanidin dimers have been found to suppress estrogen biosynthesis both in vitro and in animal models (1). Based upon this knowledge we proposed this dose finding pilot study.

Ages Eligible for Study:   55 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Age 55 - 75 years
  • Able to understand and sign a consent form
  • Postmenopausal (no menstrual period for 1 year or more)
  • No personal cancer history (except for non-melanoma skin cancer)
  • No hormone replacement therapy or anti-estrogens within 6 months of baseline

Exclusion Criteria:

  • Known allergy to grapes or grape products
  • Currently on ACE inhibitors, methotrexate, allopurinol, coumadin (Warfarin, Jantoven), heparin, clopidogrel (Plavix), or cholesterol lowering medication
  Contacts and Locations
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Please refer to this study by its identifier: NCT00566553

United States, Minnesota
Mayo Clinic
Rochester, Minnesota, United States, 55905
Sponsors and Collaborators
Mayo Clinic
Principal Investigator: Dietlind L. Wahner-Roedler, M.D. Mayo Clinic
  More Information

Additional Information:
Responsible Party: Dietlind Wahner-Roedler, Principal Investigator, Mayo Clinic Identifier: NCT00566553     History of Changes
Other Study ID Numbers: 06-009628
Study First Received: November 30, 2007
Last Updated: January 4, 2012

Keywords provided by Mayo Clinic:
Grape Seed Extract
Breast Cancer
Estrogen Levels
Aromatase Inhibitor

Additional relevant MeSH terms:
Grape Seed Extract
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs
Antineoplastic Agents, Phytogenic
Antineoplastic Agents
Molecular Mechanisms of Pharmacological Action
Protective Agents processed this record on May 25, 2017