There's no good evidence that it's any better than placebo

Popular media would have us believe that plant constituents with a phenolic structure similar to oestrogen, known as phyto (plant) oestrogens, provide a natural alternative to the use of postmenopausal hormone replacement therapy. Are the popular media right?

Phytoestrogens, found in a wide variety of edible plants, may display both oestrogenic and antioestrogenic effects. Epidemiological studies, primarily comparing Asian and Western populations, have been interpreted to indicate that consumption of a diet rich in phytoestrogens ameliorates oestrogen deficiency symptoms in postmenopausal women—and may protect against breast cancer, bone loss, and cardiovascular disease. Consequently there is a global movement towards increased consumption of foods rich in phytoestrogens, and tablet formulations of concentrated isoflavone extracts are being heavily promoted. However, more recent intervention studies question the validity of the proposed benefits of phytoestrogen supplementation, with little data in postmenopausal women to support a role for phytoestrogens as an alternative to conventional hormone replacement therapy.

The biological actions of these compounds are extremely complex. Their ultimate cellular actions are determined by many factors, including the relative levels of oestrogen receptors α and …