Extracts of various species of the Polygonaceae family have estrogenic properties. For example, aqueous and ethanolic extracts of Rheum palmatum L of the Polygonaceae family species possess estrogenic properties in both ER.alpha.+ and ER.beta.+ cells. These estrogenic effects include estrogen response element (ERE) stimulation as well as tumor necrosis factor (TNF) repression. Methods are provided for treating climacteric symptoms, breast and/or uterine cancer, and osteoporosis.