Thursday, July 20, 2006

Déjà Vu Research

Yet another study has come out purporting to expose the ineffectiveness of echinacea, the very popular botanical medicine for the common cold. "I told you so," say those who defend their cocktails of decongestants, antihistamines and analgesics. But before you throw your echinacea bottle in the trash and rush to the pharmacy, let's take a closer look at exactly what researchers did and did not discover this time around. To sort out the results, I spoke with two of the top herbal experts in the country -- Francis Brinker, ND, author of Complex Herbs, Complete Medicines (Eclectic), and Mark Blumenthal, founder and executive director of the American Botanical Council. They were in agreement that this was by no means the definitive trial on echinacea, though Blumenthal did point out that while he doesn't question the accuracy of this specific study, the results apply only to a particular type of echinacea used at a particular dosage in a particular population. Both he and Dr. Brinker advise consumers to see the results for what they are in this narrow context, rather than leaping to sweeping, simplistic conclusions -- as many mainstream media critics of natural medicine have already done -- that "echinacea doesn't work."

About the Research
In the double-blind, randomized, placebo-controlled trial, 437 student volunteers at the University of Virginia were given about one-third the dose of echinacea considered effective by US experts or a placebo. Next they were deliberately exposed to a particular type of rhinovirus that causes colds, and sequestered in hotel rooms for two weeks. Researchers found that those who were given echinacea did not experience fewer colds, fewer symptoms or a reduction in the duration of symptoms, compared with those who were given a placebo. The results of this federally funded study were published in the July 28, 2005, edition of The New England Journal of Medicine.

A Limited Study
Although the trial was accurate insofar as it went, our experts told me that there were significant limitations...
Type of echinacea. The study utilized extracts of the root of a species of echinacea known as Echinacea angustifolia. However, Blumenthal points out that there are many different species of echinacea available (Echinacea angustifolia, Echinacea purpurea, etc.)... different parts of the plant (aboveground versus roots)... different preparations (juice, alcoholic extract, pills, etc.)... and different dosages -- and they are not biochemically equivalent. This study narrowly examined low doses of one that was made in a university lab, rather than a commercial remedy that you might go out and buy in a local health-food store -- yet universal results are being assumed from the study. In fact, while Echinacea angustifolia root has been quite popular, recently there has been a trend away from its use due to ecological concerns about the conservation and sustainability of wild medicinal plants. Because Echinacea angustifolia is more difficult to cultivate commercially, products you find in stores today are apt to contain Echinacea purpurea, which was not tested.
Daily dosage. The dosage of echinacea used in the trial was 1.5 milliliters (ml) three times a day, which represents 300 mg per dose (900 mg daily). Dr. Brinker notes that this dosage is on the low side, particularly following the onset of symptoms. He told me that while you might use a low dose like this for general prevention, once you felt like you were getting sick you would take more. In fact, the dosage used in the study was a fraction of the one recommended by the World Health Organization (WHO), which is a total daily dose of 3 g.
Frequency of administration. The trial should have optimally tested echinacea at more frequent as well as higher doses, notes Blumenthal. He explains that more frequent dosing is recommended when you feel as if you're coming down with a cold or flu. A more typical dose is six times daily -- or even more -- rather than the three times daily used in the study.
Participants in the trial. Researchers studied echinacea in young, healthy college students. Yet this is not the population most likely to benefit from its use, notes Dr. Brinker, since they already enjoy robust health and competent immune systems. It would have made more sense to study echinacea's ability to enhance immunity in people who were older and more susceptible to colds to see the impact echinacea would have on those who are more vulnerable to illness.

One Piece of the Puzzle
Used intelligently and appropriately, echinacea continues to be one of Dr. Brinker's favorite botanical medicines. He told me that it works particularly well in combination with other immune-enhancing herbs, such as goldenseal. And don't overlook the fact that echinacea can function as a valuable alternative to antibiotics, which in recent years have been so overprescribed and overused that doctors fear they will no longer be effective when we really need them. When you have a cold is a good occasion to take echinacea, because antibiotics are often wrongly prescribed for colds and do nothing for them. Even when you have a bacterial infection following a cold (for example, sinusitis), when antibiotics are useful, echinacea can complement their use by pumping up your immune system.

Echinacea Rx
For the best results, buy Echinacea angustifolia root and/or Echinacea purpurea herb extract. Several quality product sources are: Eclectic Institute, HerbPharm, and Herron. "Take for to six doses daily with water or herb tea for three days, then one dose three times a day," advises Dr. Brinker. One dose is 1,000 mg of dried root in capsules or tablets or 1 teaspoon (5 ml) of echinacea alchoholic extract. Fresh freeze-dried root in capsules provides the most complete reliable source. Though there's no proven benefit to popping a daily dose of echinacea for prevention, you can use it for extended periods without worry. There are very few side effects, aside from stomach upset in some people. Some critics have cautioned against taking echinacea if you have ragweed allergies. When all is said and done, Dr. Brinker believes that the government-funded study fills in one piece of the puzzle about echinacea -- using small doses of a whole plant extract on an infrequent basis probably won't help otherwise healthy people when exposed to a virus. However, he emphatically believes that taking this limited and narrow information and making a blanket statement from it that "echinacea doesn't work" makes no sense at all.


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