- Phytoestrogens are substances found in plants (phyto-) that have estrogen-like properties.
- Phytoestrogens are found in numerous foods, most prominently soybeans (and many other types of beans), red clover, Flax Seed, and whole grains. The phytoestrogens found in these foods include isoflavones and lignans. Herbs with high phytoestrogen content include alfalfa , hops , licorice , thyme, and verbena. 1,2 Certain herbs that are often claimed to contain phytoestrogens actually do not. These include wild yam , saw palmetto , and chasteberry . Dong quai , ginseng , and black cohosh do not appear to contain phytoestrogens in the ordinary sense, but might contain substances that mimic some of the actions of estrogen under certain circumstances.
- Phytoesterogens latch onto the receptor sites on cells meant for estrogen. This results in a partial stimulation of those receptors, less intense than if true estrogen had attached, but stronger than if nothing had stimulated those receptors at all. This leads to a dual result. In women who have considerable estrogen, high consumption of phytoestrogens tends to occupy the receptor sites and keep real estrogen away. The net effect is to reduce the overall action of estrogen. Since estrogen promotes a number of forms of cancer (such as breast cancer), this may reduce cancer risk. However, in women who have little estrogen (after menopause, for example), consumption of large amounts of phytoestrogens will tend to mimic the effect of the missing estrogen, reducing symptoms such as hot flashes.