Herbs and Phytoestrogens

Many women, concerned about the health risks of synthetic hormones in conventional hormone therapy, are looking for natural alternatives. It's very important to know that products are not necessarily safe just because they're natural. The same questions we ask about drugs need to be answered for alternative therapies too: what is the specific reason to take it? Are there studies showing that it's effective for the recommended purpose? What are the risks associated with it?
 
Manufacturers of herbs and other dietary supplements are not required to provide evidence of safety or effectiveness the way they are for drugs. A recent report by the Institute of Medicine (IOM) pointed out the dangers posed by lack of reliable information about such products and by lack of quality control over manufacturing. The IOM called for legislative changes to improve accuracy in labeling and stronger protections for consumers.
 
Alternative products are less likely to have been studied than conventional drugs because many of them cannot be patented and therefore have lower profit potential. But it is still important to learn what is known about natural products and consider any safety concerns in order to be able to make an informed decision. Particularly when it comes to relieving specific symptoms, as opposed to generally improving health, women may reasonably choose to try an alternative product with less evidence than they would demand for a pharmaceutical.
 
But it's still important to consider promotional claims for these alternatives with a critical eye. Just as pharmaceutical companies promote drugs, there is a large industry of companies that produce and sell alternative health care products. Alternative health care practitioners are subject to similar influences from these companies as conventional doctors are from drug companies. Whether they are recommended by a doctor, a nurse practioner, a naturopath or the cashier at the health food store, women should be skeptical of products that claim they will extend life, reverse aging, restore youth or prevent disease without causing and adverse effects.
 
This fact sheet provides a brief overview of the National Women's Health Network's perspective on two types of alternative products promoted for women at menopause: herbs and phytoestrogens.
 
Herbs
Black cohosh, chaste-tree berry, dong quai, evening primrose, ginkgo, ginseng, licorice and red clover are among the most popular herbs for women experiencing problems with menopause. Some of these herbs have powerful hormone-like effects, and they should not be assumed to be harmless. There are very few clinical studies on their efficacy and safety.
 
In some studies of black cohosh, women got relief from hot flashes and improvements in vaginal lubrication. This is a short-term solution, however, because there are no published human studies on its long-term safety and no published study in which it's been taken for longer than six months. Studies of gingko show that it may help relieve forgetfulness, but it should not be used by people taking anticoagulants or with bleeding problems because it can cause bleeding.
The other herbs mentioned above have not been found to be effective for relief of menopause symptoms. Most have only been looked at only in small or poorly designed studies. Chaste-tree berry and licorice have not been studied for menopause relief at all.
 
Phytoestrogens
Phytoestrogens are estrogens that occur in some plants. Foods containing phytoestrogens include beans, soy products, peas, lentils, and whole grains and seeds, especially flaxseed, rye and millet. Most, but not all, studies have shown that eating foods with phytoestrogens provides relief from hot flashes. Some studies also found that eating phytoestrogens relieves vaginal discomfort. In animals, use of phytoestrogens reduces cardiovascular disease risk; and in humans, soy protein has been found to reduce cholesterol levels.
 
Although there's not a lot of evidence about health risks from clinical trials, thousands of years of dietary experience indicates that eating foods containing phytoestrogens is safe. Unlike pharmaceutical estrogens, the phytoestrogens in food do not appear to increase the risk of endometrial cancer. The risks of long-term use of nonfood phytoestrogens, like phytoestrogen supplements or red clover pills, however, are not known, and the Network discourages their use.
 
Conclusion
There is no magic bullet that will safely treat the varied health concerns of women at menopause. Women who want to try non-hormonal alternatives should look for the available evidence and test out options, starting with those that carry the least known risk, to find what works for them.
Updated: 2/05