Phytoestrogen supplements are made of plant hormones, and are often used for two main purposes. They are used by some infertile women who are going through the in vitro fertilization (IVF) process, and they may also be taken for relief of menopausal symptoms. Phytoestrogens are found naturally in a number of foods and herbs, especially soy products. These weak estrogens are similar to those produced by the human body, but are not identical.
In the body, phytoestrogen can produce different results depending on the amount taken. In lower doses, it may mimic the action of estrogen in the body, while higher doses may block the hormone. It is believed that phytoestrogens activate the estrogen receptors in the body in many cases.
There a number of different types of phytoestrogens, but isoflavones, found mostly in soy products, have most interested doctors. Studies are still being performed to determine the most beneficial level of the natural hormone therapy, but soy products are suggested to have effects on some cancers, and may influence cardiac function and bone strength. Some research has also suggested that phytoestrogens can help reduce cholesterol, particularly LDL.
There have been some studies done that indicate phytoestrogen supplements may help women undergoing IVF. In a small study posted by Bastyr Center for Natural Health, women who were given isoflavones along with progesterone had a higher delivery rate versus those given progesterone and a placebo. The Center cautioned that further studies are still needed to know how phytoestrogen supplements exactly interact with the reproductive system.
Phytoestrogen supplements are used by some women who suffer from menopausal symptoms, including hot flashes, which can be painful and irritating. Some studies have suggested that phytoestrogens may reduce the number of hot flashes a woman suffers, although the evidence is not conclusive. There is no evidence that phytoestrogen supplements reduce other menopausal symptoms, like anxiety or insomnia.
Research into phytoestrogen and phytoestrogen supplements is ongoing, particularly with regards to their impact on different types of cancer. High doses of phytoestrogens are generally not recommended by most experts, as they may have the opposite impact of what is intended. Doses of about 50 mg a day are believed to be safe, although there are no long-term studies on regular use. A number of experts in the field suggest that ingesting phytoestrogens in the diet is more likely to have a positive impact than taking phytoestrogen supplements.