Know Cancer

forgot password

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

55 Years
75 Years
Not Enrolling
Breast Cancer

Thank you

Trial Information

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

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.

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

Type of Study:


Study Design:

Allocation: Randomized, Endpoint Classification: Pharmacokinetics/Dynamics Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment

Outcome Measure:

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.

Outcome Time Frame:

12 weeks

Safety Issue:


Principal Investigator

Dietlind L. Wahner-Roedler, M.D.

Investigator Role:

Principal Investigator

Investigator Affiliation:

Mayo Clinic


United States: Institutional Review Board

Study ID:




Start Date:

February 2008

Completion Date:

September 2011

Related Keywords:

  • Breast Cancer
  • Grape Seed Extract
  • Breast Cancer
  • Estrogen Levels
  • Aromatase Inhibitor
  • Breast Neoplasms



Mayo Clinic Rochester, Minnesota  55905