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

The Effect of Grape Seed Extract on Estrogen Levels of Postmenopausal Women: A Pilot Study

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00566553
Enrollment
39
Registered
2007-12-03
Start date
2008-02-29
Completion date
2011-09-30
Last updated
2012-01-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Cancer

Keywords

Grape Seed Extract, Breast Cancer, Estrogen Levels, Aromatase Inhibitor

Brief summary

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.

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.

Interventions

DIETARY_SUPPLEMENTGrape Seed Extract

200 mg dose daily for 12 weeks.

Sponsors

Mayo Clinic
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Age
55 Years to 75 Years
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

Design outcomes

Primary

MeasureTime frame
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.12 weeks

Secondary

MeasureTime frame
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).12 weeks

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026