Phytoestrogens benefit for menopause, hot flashes, soy pill
Phytoestrogens are non-steroidal plant molecules whose structure differs from gonadal hormones, but with an estrogen-type bioactivity: they are capable of interacting with estrogen receptors, showing both agonist and antagonist methods of action. The beneficial effects of various classes of phytoestrogens present in nature are now known, but the main isoflavone present in soy, genistein, appears to be particularly effective. Interest in this substance is concentrated in particular on its therapeutic role in menopause. A diet rich in isoflavones is associated with a reduced incidence of vasomotor episodes; the average supplement of genistein is approximately 50 mg/day. After supplementing the diet with phytoestrogens, studies show a reduction in total cholesterol and LDL fraction. This is accompanied by an increase in bone mineral density after taking 90 mg of isoflavones for 6 months. Isoflavones may reduce the risk of developing breast cancer. The data examined confirm the excellent clinical efficacy of supplementing the diet with soy extracts, particularly genistein which is indicated to alleviate both the short-term symptoms of menopause and the long-term effects, although the latter finding requires further substantiation.

Common phytoestrogens
 Some of the well-known phytoestrogens include genistein, daidzen, coumestrol and zearalenone. There are many plants that have phytoestrogens, for instance hops.

Benefits

Blood pressure
The effects of phytoestrogen on blood pressure and lipids in healthy volunteers.
Zhonghua Xin Xue Guan Bing Za Zhi. 2006 Aug. Cardio-Lungs-Vascular Center, Tongji University, Shanghai 200433, China.
To determine the effects of dietary soy containing phytoestrogens on blood pressure and lipids in healthy volunteers. Two hundred thirteen healthy volunteers (108 men and 105 post-menopausal women, 50 - 76 years old) received either soy protein isolate (40 g soy protein, 118 mg isoflavones) or casein placebo for 3 months in this randomized, double-blind trial. In normotensive men and post-menopausal women, phytoestrogens intake improved blood pressure and lipids status.

Colon cancer
Dietary phytoestrogen Intake Is associated with reduced colorectal cancer risk.

Heart disease
High intake of phytoestrogens in postmenopausal women appears to be associated with a favorable metabolic cardiovascular risk profile. A Western diet rich in tofu and other soy products may help protect older women from heart disease.

Effects of the phytoestrogen genistein on some predictors of cardiovascular risk in osteopenic, postmenopausal women: a two-year randomized, double-blind, placebo-controlled study.
J Clin Endocrinol Metab. 2007 Aug. Department of Internal Medicine, University of Messina, Italy.
Our objective was to assess the effects of phytoestrogen genistein administration (54 mg/d) on some predictors of cardiovascular risk in osteopenic, postmenopausal women. Participants were randomly assigned to receive genistein or placebo daily for 24 months. Both intervention and placebo contained calcium and vitamin D(3). Compared with placebo, genistein significantly reduced fasting glucose and insulin as well as homeostasis model assessment for insulin resistance after both 12 and 24 months of treatment. By contrast, genistein administration did not affect blood lipid levels although fibrinogen, F2-isoprostanes, soluble intercellular adhesion molecule-1, and soluble vascular cellular adhesion molecule-1 decreased significantly compared with placebo after 24 months. Serum osteoprotegerin was higher in the genistein group compared with placebo. At 24 months, the genistein group showed no change in endometrial thickness compared with placebo. These results suggest that 54 mg genistein plus calcium, vitamin D(3), and a healthy diet was associated with favorable effects on both glycemic control and some cardiovascular risk markers in a cohort of osteopenic, postmenopausal women.

Menopause - Do phytoestrogens help reduce the severity or frequency of hot flashes?

In a study conducted at the University La Sapienza in Rome, Italy, postmenopausal women were given phytoestrogen tablets containing 60 milligrams of isoflavones for 6 months and compared to women who received placebo pills. The women receiving the phytoestrogens did better on measures of mental performance and mood. When asked which treatment they preferred, 49 women favored the phytoestrogen pill, 9 favored placebo, and 18 had no preference. The researchers say, "The current findings suggest a possible role for phytoestrogens in relieving the psychological disturbances often associated with the complex symptomatology of menopause."
   Another study continues to raise cautions about the long term use of estrogen. Women who took estrogen-only pills for at least 15 years had a higher risk of developing breast cancer, according to a study of nearly 29,000 nurses. But no increased danger was found among those who took the hormone for less than 10 years.
   Comments: There has been controversy regarding the role of phytoestrogens in the treatment of symptoms of menopause for quite some time. If you plan to take phytoestrognes, try a lower dose first before moving on to higher amounts. You may consider at first using half the dose used by the researchers and take a day or two off a week. If you are using estrogen, use as low a dose as possible for as short a time as possible.
 

Effects of the phytoestrogen genistein on hot flushes, endometrium, and vaginal epithelium in postmenopausal women: a 1-year randomized, double-blind, placebo-controlled study.
 Menopause. 2007 Jul-Aug. Department of Obstetrical and Gynaecological Sciences, University of Messina, Messina, Italy.
To evaluate in a 12-month, prospective, randomized, double-blind, placebo-controlled study whether pure administration of the phytoestrogen genistein (54 mg/d) might reduce the number and severity of hot flushes in postmenopausal women with no adverse effect on the endometrium. The phytoestrogen genistein was shown to be effective on vasomotor symptoms without an adverse effect on endometrium.

 

Osteoporosis
Effects of the phytoestrogen genistein on bone metabolism in osteopenic postmenopausal women: a randomized trial.
Ann Intern Med. 2007 Jun 19;146(12):839-47. Azienda Ospedaliera Universitaria Policlinico G. Martino, University of Messina, Messina, Italy.
Observational studies and small trials of short duration suggest that the isoflavone phytoestrogen genistein reduces bone loss, but the evidence is not definitive. 389 postmenopausal women with a bone mineral density (BMD) less than 0.795 g/cm2 at the femoral neck and no significant comorbid conditions took 54 mg of phytoestrogen genistein daily for 24 months. Both the genistein and placebo tablets contained calcium and vitamin D. Twenty-four months of treatment with genistein has positive effects on BMD in osteopenic postmenopausal women.

Adding to evidence of the potential benefits of so-called plant estrogens, a study suggests that isoflavone supplements may help reduce menopausal bone loss. UK researchers found that, when taken for a year, the supplements appeared to curb spinal bone loss in women between the ages of 49 and 65. Isoflavones, compounds found in soybeans, chickpeas and other legumes, are similar to the female hormone estrogen. Because of this, researchers have been studying whether soy protein or supplements containing isoflavones might act as a sort of "natural" hormone replacement therapy.

Studies have shown that Asian women, whose traditional diet is rich in soy, have a relatively low rate of hip fracture, as well as breast cancer and heart disease. In addition, animal research has suggested that isoflavones might lessen bone loss related to waning estrogen levels. Some studies of women, however, have found no evidence of bone benefits, and much of the research on isoflavones has involved only small groups of women followed for a relatively short time. The study followed 177 women for a year and is one of the largest and longest investigations of an isoflavone supplement to date, according to the authors. They found that compared with women randomly assigned to take a placebo, those who took a daily isoflavone tablet showed less bone loss in the lower spine.

Hormone replacement therapy and menopause
Recent studies indicate that long term replacement with Premarin (horse derived estrogens) and synthetic progesterone increases the risk for heart disease, cancer, blood clots and gallbladder disease. 

What is the opinion of the medical establishment?
The field of hormone or herbal therapy during or after menopause is very complicated and there is no consensus within the medical community regarding the best option for long term therapy. The medical community seems to be shifting its viewpoint on hormone replacement. It appears that most traditional doctors now prefer using low doses of hormones for a brief period of time to treat menopausal symptoms, but prefer not to continue hormone replacement therapy indefinitely as in the past.

Phytoestrogen questions
Q. What is the phytoestrogen content of pomegranate pill by Club Natural?
   A. The phytoestrogen content of pomegranate is not something that is routinely tested.

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