Herbs are huge. But which ones really work?

Sales of herbal remedies are booming. In part this is because the numerous (albeit rare) side effects of over-the-counter and prescribed medications described in ads and package inserts are scary.  Another reason is the scramble to all things “natural.” The other is price -– in general herbs are much cheaper than man-made drugs, especially for those not covered by an insurance plan. But are they effective and, more important, safe? Here, “Today” medical contributor Dr. Judith Reichman reviews some of the more popular herbal therapies used by women.  Some may be good for you, others useless and a few truly harmful.

What exactly are herbal remedies, how are they made and how are they regulated?Herbs for medicinal use, called botanicals, are farmed or gathered and then processed to yield the “active components”. Bear in mind that there are many different parts of the plant -- the leaves, bark, flowers, seeds, roots and oils -– and each component varies in content and potential effect (or lack of effect). And plant varieties differ -– the potency and absorption of an ingredient can change from plant to plant, season to season and plot to plot. Since the therapeutic ingredient(s) often have not been identified, standardization is nearly impossible. Finally, there is no FDA regulation.  These herbal products are categorized as dietary supplements and as such the FDA does not supervise their safety, purity or effectiveness the way it does for prescription or over-the counter medications. The manufacturers of herb products do not have to obtain FDA approval in order to market them.  They are free to proclaim that their product promotes, enhances and supplements our physiologic processes and well being, just as long as they don’t say that it treats a disease.  In small print you’ll find a qualifier that: “This statement has not been evaluated by the Food and Drug Administration.”

Aren’t there some agencies that have looked at herbal therapies and have evaluated their effectiveness?In Germany, about 30 percent of the drugs sold in pharmacies are herbal. There is an oversight commission called the German Commission E that tries to establish whether an herbal product is safe within “reasonable certainty.”  In this country, the National Institute of Health’s Center for Complimentary and Alternative Medicine is studying selected herbs in clinical trials.  There is also a Natural Standard Research Collaboration that uses 400 researchers and clinicians to review global literature and studies on herbs, and they have come up with a grading system for some of the more popular herbs. 

Unfortunately, many of the studies that are commonly cited were done for a short period of time on small numbers of women.  So the typical statement that “symptoms decrease by thirty to forty percent in the first three months” or that “thirty to forty percent of women responded” may simply represent a placebo effect or one that is only minimally better than placebo, and does not constitute proof that the product will continue to work for the long term. 

So how do some of the popular herbs used by women rate?

Soy supplementsEating soy products, such as those found in traditional Asian diets, is, indeed, healthful.  Women who grow up eating a soy-rich diet have less breast cancer.  But subsequent to puberty, once breast cells are no longer developing and have reached normal maturation, dousing them with soy, either from food or supplements, has not been found to decrease the chance that they will become malignant.  And indeed, there is concern that too much of the plant estrogen found in soy can actually increase the potential for breast cancer.  Although soy protein in food can lower the bad cholesterol (LDL), especially when consumed instead of animal protein, we’re not sure that taking a soy capsule or powder will do the same thing. 

A recent review of studies that looked at soy supplements and hot flashes showed that in the short term some women felt they had less flashes.  But long term (24 weeks or more), soy was no better than placebo.

This has shown some benefit for sufferers of hot flashes in short-term studies done by the company that makes the most widely used form of black cohash called Remifemin (Glaxo-Smith-Kline).  We’re not sure how it works. It’s possible that it may affect estrogen receptors in some parts of the body, but it certainly has no affect on others.  (It doesn’t decrease vaginal dryness in menopausal women.)  The German Commission E has approved the use of black cohash for the treatment of hot flashes, but for no longer than six months.  We’re also not sure how this product might affect women with breast cancer.  There are concerns that black cohash can interact with hormonal medications and anticoagulants.

Evening primrose oilThe seeds of the evening primrose plant produce oil that is rich in a fatty acid called GLA (gamma-linoleic acid). GLA can increase production of a substance that inhibits inflammation and hence might be a remedy for arthritis, PMS and breast tenderness (all felt to be correlated with inflammatory substances, such as wine or chocolate).  But studies have not yielded evidence that evening primrose is effective in any of these conditions. 

Red cloverThe few small studies done on red clover did not find that this herb (that is touted to be chock-full of plant estrogens) helped alleviate hot flashes.

St. John’s wortThis gets an ‘A’ for short-term treatment of mild to moderate depression, but will not work for severe depression. But, since the active ingredients in St. John’s wort are unknown, we can’t always be certain you are getting the optimal dose.  St. John’s wort has a large number of drug interactions and it can interfere with oral contraceptives.  It should not be taken casually or without medical consultation for the underlying depression.

EchinaceaOverall, this may deserve a ‘B’ because it can shorten the duration of upper respiratory tract infections, but it won’t prevent infections and should not be used long term.  Goldenseal is frequently combined with echinacea in cold preparations, but there is no evidence that it adds to its benefit.

ValerianThere are more than two hundred valerian plant species.  One that seems to help insomnia is Valeriana officinalis, and this is has a very noticeable, bad odor.  It has been shown to help you fall asleep faster and as a sleep aid gets a ‘B’ but it should not be mixed with alcohol or other sleep medications.  It can also interact with other drugs.

CranberryCranberry juice and cranberry extracts have been found to decrease the ability of bacteria to adhere and multiply on the bladder wall and in general may help prevent bladder infections.

There are currently no good studies to show that this helps menopausal symptoms.  Although many pharmaceutically manufactured estrogen and progesterone therapies are produced from wild yam, that doesn’t mean that what is processed into the “pure” herbal product will work.  When it comes to wild yam creams, the progesterone needs to be extracted through a lab process and cannot be absorbed through the skin, so these creams are probably no better than moisturizers.

GingerThis can help treat pregnancy-related nausea and nausea induced by chemotherapy, but it has not been shown to help with motion sickness or nausea after surgery. 

Are all herbs safe?Remember, hemlock is an herb.  Other herbs have been found unsafe and banned from legal sale in the USA because they can cause severe side effects and even death.  Most recently, ephedra, which has been linked to irregular heart rhythm, high blood pressure, heart attack and stroke culminating in death, has been banned in this country. 

Because additional analysis, research and testing is needed before we can tell the consumer whether an herb works and is truly safe, and because regulation of what’s in the herbal preparation is not stringent, I advise women not to become “herbalized” by overly enthusiastic advertising and product promises.  And always make sure you discuss what you’re taking, or plan to take, with your doctor.  Don’t bet your health on recommendations by a sales clerk who will be more than happy to ring up an herbal supplement sale!

Dr. Judith Reichman, the “Today” show's medical contributor on women's health, has practiced obstetrics and gynecology for more than 20 years. You willl find many answers to your questions in her latest book, "Slow Your Clock Down: The Complete Guide to a Healthy, Younger You," published by William Morrow, a division of .