Studying the Effect of Freeze-Dried Table Grape Powder on Blood Estrogen Levels in Postmenopausal Women

OBJECTIVES:

• To measure the change in levels of plasma estrone (E1), estradiol, E1-conjugates, and E1-sulfates in postmenopausal women after 6 weeks of daily ingestion of 94 grams of freeze-dried table grape powder.
• To conduct bioavailability research on the freeze-dried table grape powder in humans through the analysis of participants' blood and urine samples.

OUTLINE: Participants receive oral freeze-dried table grape powder once daily on days 1-42 in addition to their usual diet. Treatment continues in the absence of toxicity.

Participants undergo blood sample collection at baseline, periodically after the first dose, and on the last day of the study for pharmacokinetic and bioavailability analysis. Samples are examined by mass spectrometry to measure plasma levels of estrone (E1), estradiol, E1-conjugates, E1-sulfates, testosterone, and androstenedione. Participants also undergo spot urine collection and weight and height measurement periodically during study.

Participants complete food diaries on days 1-3, 21-23, and 40-42 to assess their intake of grapes, grape juice, and red wine and to examine the constancy of their caloric intake over the course of the study.