The two phytoestrogens that have been the most thoroughly studied;

Phytoestrogen and Soy

There is growing evidence that eating foods rich in phytoestrogens (plant substances that have an estrogenlike activity) can be of significant help in easing the symptoms of menopause. Soy base plant and herb are high in phytoestrogens.

Women in cultures that traditionally eat a lot of soy products, such as the Japanese culture, have a much lower incidence of difficult menopausal symptoms. This appears to be, at least in part, because foods rich in phytoestrogens mimic estrogen activity in the body.

First
They "satisfy" the receptor by binding to it. This allows the receptor site to respond by initiating changes within the cell. These changes could include helping to decrease osteoporosis, in the case of bone cells, or decreasing hot flash symptoms, in the case of blood vessels. The effect is not nearly as strong as that of a steroid hormone like estradiol, but sometimes that is better.

Second
Phytoestrogens decrease cancer stimulation by steroid hormones such as estrogens by taking up the receptor space and competing with steroid hormones that would normally bind to the hormone receptors. When phytoestrogens block steroid estrogens from binding to the receptor, they are said to be antagonists, meaning they work against the steroid hormones. This effect could prevent strong stimulation of cancer cells in the breast or uterus.

With less stimulation from steroid estrogens, cancer cells will grow much slower and may be more susceptible to control by the immune system. Additionally, research reports that some phytoestrogens, such as genistein from soybeans, actually suppress tumour growth even in tumours that are not influenced by hormonal activity.

Soy is the most well studied of foods containing phytoestrogens, and is the source of several very important substances such as the isoflavones, genistein, and daidzein. As well as decreasing cancer risks, soy has the ability to help prevent osteoporosis and, possibly, autoimmune diseases.

Since phytoestrogens have an antagonist effect, the decreased risk of autoimmune disease should come as no surprise. It is well-known that women have a higher incidence of autoimmune diseases than men, and that estrogens are believed to play a role in these conditions.

The isoflavones, genistein, and daidzein could prevent postmenopausal bone loss and osteoporosis. In animal studies, genistein is as effective as steroid estrogens in preserving bone. Even synthetic isoflavones, such as ipriflavone, are able to reduce bone loss in animals with osteoporosis and show great promise for the prevention and treatment of postmenopausal osteoporosis.

Animal research demonstrates that soybean phytoestrogens do not have any estrogenic activity in the uterus and vagina, and exert antagonist activity by reducing uterine cell stimulation by supplemented steroid hormones.

The implications are that women on hormone replacement would benefit from taking soy based phytoestrogens. A healthful diet that includes regular intake of legumes may result in a decreased risk of endometrial cancer. In addition to decreasing risks of breast cancer, uterine cancer, heart disease, and osteoporosis, soy can relief some of the more immediate discomforts of menopause.

Based on a 1991, Journal of the National Cancer Institute, estimates that 1 cup of soybeans provides about 300 mg of plant estrogens called isoflavones the equivalent of about 45 mg of conjugated estrogens, as potent as a low to medium dose of the prescribed estrogen, Premarin.

Research also suggests that switching to certain drugless therapies can also contribute to managing and treating these diseases once they have occurred. Certain nutritional supplements may protect the body from the harmful effects like bone loss and heart ailments.

Soy foods are a good source of protein and it's becoming easier and more pleasant to eat some everyday, preferably in place of animal foods. There are now several types of tofu or soy burgers on the market, flavoured and unflavoured soy milks (they work in shakes, on cereals, in cooking, and even in hot beverages such as tea), in addition to low-fat versions of tofu in firm, regular, and soft consistencies.

Some soy foods may have more plant estrogens than others. Many women have reported relief of menopausal symptoms when they eat these foods.