Many women rely on black cohash, wild yam and the Chinese herb Dong Quai as alternative therapies to ease the symptoms of menopause, but a leading medical organization says there is little scientific evidence that these and other natural therapies actually work.
As many as 30 percent of women turn to acupuncture or natural products for relief of menopausal symptoms, according to the North American Menopause Society. Herbs and other botanicals, such as soy products, are heavily marketed in the United States as alternatives to hormone replacement therapy.
"We know the (manufacturers') claims are manifold and sweeping," says Dr. Maida Taylor, the author of a paper released by the American College of Obstetricians and Gynecologists. "Some things have merit and others do not. Doctors need to advise their patients with some foundation."
The report was published to help doctors counsel women who are taking alternative therapies to alleviate menopausal symptoms such as hot flashes, sleep problems and mood swings.
Women who prefer using natural products or seek alternatives to hormone therapy may be disappointed that the guidelines find merit in only a few botanical therapies. The biggest problem with natural products, says Taylor, is the lack of scientific evidence demonstrating they work.
"I think women are suspicious of hormones," says Taylor, an associate clinical professor at University of California of San Francisco. "The alternative (products) are viewed and promoted, in many instances, as providing all of the benefits of hormones without any of the attending risks."
In fact, women may be risking their health by using specific botanical products. Valerian root, for example, is touted as a sleep aid but has not been proven effective for that use. The herb has also been linked to heart problems and severe withdrawal symptoms, according to the ACOG paper.
Another popular therapy may lead women into a potentially risky situation, says Taylor. Some women use "natural" progesterone cream products along with prescription estrogen to offset the risks of taking estrogen alone. Taking estrogen alone can increase the risk of uterine cancer, so doctors typically prescribe prescription progesterone too.
But studies show that natural progesterone creams aren't effective to offset the risk of taking estrogen by itself, she says.
"Women are told that they can take this progesterone cream instead," says Taylor. "That is a very popular fad."
Wild yam and Mexican yam creams also are touted as helpful for menopausal symptoms. But studies show there is nothing in natural yam creams that would alleviate hot flashes or other symptoms. Some yam creams are adulterated with progesterones. But "the amount absorbed is highly variable and unpredictable," Taylor says. "Therefore, it can't be recommended as a therapeutic option with a predictable outcome."
The ACOG report does not dismiss botanical therapies outright, however, saying that soy and black cohash, when used for hot flashes, and St. John's wort, when used for mild to moderate depression, may have limited use.
"It's not that botanicals are devoid of benefit," Taylor says. The benefits, though, "are at a much lower level and a narrower bandwidth."
Taylor notes, however, that natural products are not subject to the same regulatory oversight in the United States as are prescription drugs. Therefore, it's possible that some herb products may not contain what is stated on product labels.
For example, the ACOG paper cites a 1998 study of 54 ginseng products that found most had little or no ginseng. Some were heavily adulterated with caffeine.
Manufacturers of herbal products are also free to make a variety of claims about their products without proving the accuracy of those claims, says Pamela Boggs, director of education for the North American Menopause Society.
"Unfortunately, consumers are being misled because of the different requirements of the prescription products vs. the botanicals. Prescription drug makers can't make a claim without the Food and Drug Administration's approval. That isn't the case with botanicals."
Natural products manufacturers can make truthful claims about the effect of a supplement on the body's structure or function, such as "promotes good sleep." They can also refer to symptoms associated with certain life stages, such as: "for hot flashes associated with menopause."
Natural products cannot carry disease-related claims, although the FDA in 1999 permitted manufacturers to claim that foods rich in soy could help lower the risk of heart disease.
The effects of hormone therapy on serious diseases such as breast cancer and heart disease is unclear. Although observational studies strongly suggest that hormone therapy helps protect against heart disease, the association has not been proven.
The link between hormone therapy and breast cancer is also unclear, although most evidence suggests that estrogen has little impact on the development of breast cancer.
Hormone replacement therapy, however, is usually very effective for the relief of hot flashes, night sweats, fatigue and vaginal dryness. It also helps protect against osteoporosis.
However, the Herb Research Foundation, a nonprofit consumer education group that promotes the medicinal use of herbs, disagrees with some of ACOG's conclusions, particularly the paper's reliance on studies by U.S. researchers.
"If they are going strictly on studies done in the United States, there just aren't as many as have been done in Europe," says Mindy Green, director of education for the Boulder, Colo., foundation.
The ACOG guidelines also place unreasonable limits on the use of some substances, such as soy and black cohash, she charges. For example, studies on women taking black cohash for six months found it to be effective for hot flashes. Therefore, ACOG recommends use of the herb for only six months. But there is no evidence the herb stops working after six months, Green says.
Some of these questions may be cleared up soon. The number of well-designed studies done on herbs has doubled within the last few years, says Taylor. And the National Center for Complementary and Alternative Medicine is funding research on black cohash, Chinese herbs, flaxseed and soy, among other botanicals.