A top executive in the dietary supplement industry concedes he was "a little concerned" upon learning that the powerful American Medical Assn. would scrutinize alternative medicines such as herbal therapies.
After all, organized medicine for years dismissed the acupuncturists, herbalists and naturopaths of the world as little more than charlatans. And the views of the two camps about what constituted "good medicine" were hardly similar.
But the slate of articles on herb therapies appearing this month in a half-dozen AMA specialty journals may represent something of a peace offering. The authors of nearly a dozen papers give a surprising nod of approval to the use of several popular herbs--although with reservations.
"I am delighted," said Loren Israelsen, executive director for the Utah Natural Products Alliance, an industry trade group. "I really think this is a breakthrough. It signals a change in understanding the role of herbs in U.S. health care. For the longest time, we have begged the medical community to take it seriously and become familiar with the scientific literature."
The articles may also meet what has become a shared goal between the two health-care forces: to persuade consumers to tell their doctors when they are taking herb and vitamin supplements. Many of the journal articles comment on the need for physicians to acknowledge their patients' use of herbs.
"Historically, people have been very cautious to share that information. Now, perhaps the doctor will say, 'I appreciate the value of vitamins and herbs.' The [recent publications] legitimize that conversation," Israelsen said.
Clearly, however, physicians want to know about their patients' use of herbs because of concerns they have over the safety of many products. Virtually all the studies-- published during the past two weeks in the AMA's family of specialty journals--call for more research on herbs, particularly on the optimal dosages, and more controls on the purity and quality of processed herbs.
Despite the pitfalls of using herbs, reports on such popular botanicals as milk thistle, ginkgo and saw palmetto were generally positive.
"On all of the most popular herbs, I think there is enough evidence to warrant more study," said Dr. Mary Ann O'Hara, who conducted a review of 12 of the most commonly used herbs. The report is published in the Archives of Family Medicine.
Conventional health practitioners might underestimate the effectiveness of herbs by not realizing just how much scientific literature exists on botanicals, she said.
"There are really misconceptions on both sides--patients and clinicians," said O'Hara, a Robert Wood Johnson clinical scholar at the University of Washington. "In general, the quality of research on herbs is a problem. But there is more research on herbs than [doctors] recognize."
Consumers, meanwhile, are enchanted with the idea that herbs are more "natural" than drugs. And yet, she noted, herbs contain chemicals in the same way that drugs contain chemicals.
"A common misperception among the public--that is exploited by the herb industry--is that drugs are chemicals and herbs are not. Herbs are clearly chemicals, but they are more raw. As chemicals, they may be helpful or dangerous," she said.
Echoing the idea that herbs can behave like drugs, several of the journal pieces warned that consumers should not use herbs and other medications together without telling their doctors.
Up to 70% of patients do not reveal their herb use to their doctors or pharmacists, said Lucinda G. Miller, author of a report on drug-herb interactions in the Archives of Internal Medicine.
"Not only is the potential for drug-herb interaction unmonitored, but the concomitant use may not even be acknowledged," she said. "This phenomenon is fraught with peril. . . ."
Another problem noted in all the studies is that herbs are not subject to any regulations governing the quality or purity of the products. Herbs can vary widely, based on how they are grown, harvested, stored, processed and handled, and whether the final product is in pill or liquid form, noted University of Colorado researchers Lisa Corbin Winslow and Dr. David J. Kroll in the Archives of Internal Medicine.
They even warn that additives might be used in herbs that are not listed on the product label. Unlisted additives--such as steroids, ibuprofen, antibiotics, sedatives and narcotics--could be responsible for the effect the product exhibits.
Finally, only a few herbs have been studied to the extent that experts agree on a recommended dose and on what active ingredient should be standardized. Standardization means that a particular amount of the active chemical is present.
Roundup of Popular Herbs
As for whether an herb is even worth buying, here is a summary of the recent data, analysis and opinion published in the AMA journals on the most popular herbs.
This herb is used for arthritis pain and preventing migraines, and shows evidence of real benefit in the later case. In a randomized, controlled trial--considered the most scientifically rigorous way to conduct a study--feverfew did not reduce the symptoms of arthritis patients. But it did show benefits for migraine patients in two of three studies. One study found a 70% reduction in migraine frequency and severity.
"Based on these trials, Canadian health officials recently approved encapsulated feverfew leaves as an over-the-counter medication[to prevent migraines]," O'Hara noted in the report.
Side effects can be a problem. Thus, experts recommend a gradual dose increase up to 125 milligrams daily, standardized to 0.2% parthenoilide, the active chemical.
An analysis in the Archives of Internal Medicine suggests garlic has promise in reducing cholesterol. "The precise extent of garlic's impact on atherosclerosis [hardening of the arteries] remains controversial; large, more rigorously designed trials may be necessary to better determine its utility in preventing cardiovascular disease," the authors noted.
Also this month, a study in the Archives of Pediatric and Adolescent Medicine found no significant effect when garlic was used by children with high cholesterol levels.
Garlic is safe and generally inexpensive, O'Hara said. The usual dose is 300 milligrams taken two or three times a day, which equals about one fresh clove. Look for a label saying the product is standardized to at least 1.3% allicin.
Used to prevent nausea, ginger seemed to help women with pregnancy sickness, but studies are mixed on its effectiveness at preventing motion sickness.
"It is reasonable for patients to try ginger to treat nausea, not only because data supports its efficacy, but also because it is inexpensive, readily available and safe," noted O'Hara in the report. The usual adult dose is 250 milligrams (one-fourth of a teaspoon) to 1 gram powdered root several times per day.
In a review of 50 studies on ginkgo biloba's effects on Alzheimer's patients, only four studies were deemed to be good enough to yield reliable results. Those four studies included 212 patients, half of whom received ginkgo and half a placebo. The analysis, published in the Archives of Neurology, concluded there is a "small but significant" effect on the cognitive functioning of Alzheimer's patients in a three- to six-month period.
The usual dose is 40 milligrams three times a day, or 80 milligrams twice a day, of a product standardized to 24% flavonoids and 6% terpenoids. The products should contain the extract studied in the clinical trials called Egb 761.
"Ginseng stands out as an extraordinarily popular and quite expensive herb without clear evidence of benefit . . ." said O'Hara of the herb, which is used as a performance enhancer, anti-cancer agent and aphrodisiac.
Also, researchers noted that the quality of the product--whether it contains ginseng or not--has been a problem. Ginseng should be avoided when using stimulants or in patients with cardiovascular disease, O'Hara said.
O'Hara discourages use of this herb, even though evidence shows some effectiveness to reduce diarrhea.
"Despite the anti-diarrheal efficacy . . . we do not recommend the use of the herb goldenseal for this purpose, both because of this plant's endangered status and due to the possible toxicity of its other components," the report said.
Goldenseal is unproven as a cold remedy. Large amounts of goldenseal can cause gastrointestinal tract upset, uterine contractions, hypertension, seizures, cardiac effects and respiratory failure.
Horse chestnut extract
This herb contains an enzyme thought to reduce the symptoms of chronic venous insufficiency, such as varicose veins. A new analysis of horse chestnut extract in the Archives of Dermatology found it was better than a placebo in all studies. The herb decreased lower leg volume, leg pain, fatigue and tenderness.
"[Horse chestnut extract] represents a treatment option . . . that is worth considering," said the authors of the analysis from the University of Exeter in England. The active ingredient in this herb is called escin. Products should be standardize to 50 milligrams escin, the dose used in most trials.
This herb needs more study but has generated excitement for its possible effect on various liver disorders for which there are few conventional treatments.
"It's not clear it is a treatment, but it clearly warrants more study to see if it could be helpful," O'Hara said. The dose usually studied is a 140-milligram capsule, standardized to 70% silymarin, two to three times a day.
This is a popular remedy for prostate enlargement. Data show it is as effective as the drug finasteride with fewer side effects, according to O'Hara. The usual dose is 160 milligrams twice daily, standardized to contain 85% to 95% fatty acids and sterols.
St. John's wort
This herb has promise in the treatment of mild to moderate depression, according to an analysis in the Archives of General Psychiatry. However, more studies are needed to define which patients could benefit, to standardize preparations, and to compare the herb with antidepressants, experts said. The authors noted that St. John's wort produces fewer side effects than antidepressants, which may assist in compliance and quality of life issues for patients.
Patients should take 300 milligrams three times a day standardized to 0.3% hypericin.
(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)
The Buzz on Botanicals
New research published recently in nine American Medical Association journals gave a mixed scorecard on the effectiveness of certain herbs. Some examples:
Studies finds garlic ineffective for lowering cholesterol in children and conclude there is little evidence that it reduces risk factors for heart disease.
A small but significant improvement in cognitive function in patients with Alzheimer's disease over a three- to six-month period, studies say.
Researchers find scant evidence of its effectiveness as a performance enhancer, anti-cancer agent or aphrodisiac. And it's expensive to boot.
For enlarged prostates, there is good evidence that it is as effective as a popular prescription drug and has fewer side efects.
St. John's wort
Some evidence exists that it can benefit people with mild depression, but not enough is known about dosage and which patients would benefit, researchers say.