Cold Relief From Echinacea Might Be All in Your Head

Echinacea, the popular herbal remedy used for the common cold, does not ward off runny noses, sore throats or headaches, nor does it help speed recovery from cold symptoms, according to the results of a broad clinical trial reported today in the New England Journal of Medicine.

Taken with other recent studies that showed no benefit from echinacea, the new findings shift the burden of proof to proponents of herbal products to demonstrate that the plant has medicinal value, researchers said.

“We find no evidence that it actually does anything to common cold symptoms,” said Dr. Ronald B. Turner, a professor of pediatrics at the University of Virginia School of Medicine and the study’s lead author. “If that’s the reason you’re buying it, then you’re wasting your money.”

Echinacea enthusiasts said they did not think the results of the study merited such a sweeping conclusion. They said that Turner and his colleagues used only the root portion of one version of the plant and that the dosage given was too low to register any positive effect.

“This is a good contribution to the clinical literature, but it’s not the definitive study on echinacea,” said Mark Blumenthal, executive director of the American Botanical Council, a nonprofit group backed by herbal supplement makers. “I just wish it had been a bigger study with bigger dosages.”

Echinacea, a member of the same plant family as sunflowers and daisies, was used for hundreds of years by more than a dozen Native American tribes to treat snakebites, toothaches, coughs and other ailments.

Western doctors began recommending it in the 19th century. It became popular in the United States in the 1960s as consumers embraced herbal alternatives to traditional medicine. The World Health Organization recognized echinacea as a treatment for colds in 1999.

Americans spent $153 million on echinacea products last year, making it one of the five best-selling herbs in the country, according to the Nutrition Business Journal, an industry publication in San Diego. It comes in capsules, tablets, tonics, powders, lozenges, tea bags and even gummy vitamins for children. But spending has declined steadily since 2001 as some users have become disillusioned with it, said editor Grant Ferrier.

“With a lot of herbal botanicals, including echinacea, there’s not a tangible effect,” Ferrier said. “It’s not like taking a pill for a headache. A lot of it goes on faith.”

Widespread consumer faith in echinacea’s ability to boost the immune system prompted the National Center for Complementary and Alternative Medicine, a branch of the National Institutes of Health, to fund the two-year study. The goal was to pinpoint how the herb attacked colds, said Dr. Stephen E. Straus, the center’s director.

Instead, the study found the plant served no such role.

“I would wish nothing more than for the echinacea study to be positive, but good science speaks for itself,” Strauss said.

Turner and his colleagues tested three homemade preparations of echinacea, each designed to track the effect of a specific extract of the herb. All of the versions were derived from the root of an Echinacea angustifolia plant and contained the equivalent of 300 milligrams of echinacea per dose.

The researchers recruited 437 healthy volunteers and gave them a cold by squeezing droplets of the virus into their noses. Some of the volunteers took echinacea three times a day for one week before being infected. Others started taking it the day they were infected, and one group received a placebo throughout the experiment.

Once infected, the volunteers were sequestered for five days in hotel rooms, where their symptoms were monitored.

Among other things, the volunteers -- mostly college students -- endured daily squirts of saltwater up their nostrils. After the water was expelled into cups, researchers cultured the contents to measure the level of different kinds of antibodies.

Volunteers also were asked to give used tissues to researchers, who weighed them to determine whether patients taking echinacea produced less mucus than those on the placebo.

At the end of the study, researchers could not discern any difference between patients who took any form of echinacea and those who took the placebo.

“None of the preparations we used had any effect on either the rate of infection or the severity of illness,” Turner said.

Echinacea advocates insisted the study would have shown an effect if the dosage had been higher.

“We do a minimum of 900 milligrams three times a day,” said Dr. Mary Jo DiMilia, an assistant clinical professor of medicine at the Mount Sinai Hospital School of Medicine in New York, who described herself as a satisfied echinacea user and recommended the herb to patients. She acknowledged, however, that there were no clinical trials proving echinacea was effective at that dose.

Blumenthal, of the American Botanical Council, said the homemade compounds used in the study did “not correlate directly to any product consumers are using in the marketplace.” It would be inappropriate, he said, to assume the study’s results hold true for products made from different kinds of echinacea plants or that use the flowers and leaves instead of the root.

Turner said his team -- which included some echinacea devotees -- stayed away from off-the-shelf products because they couldn’t determine what was in them. The echinacea dosages they used were recommended by a government panel in Germany.

“Do I think it’s likely that other echinacea preparations will have an effect given the results here and in other studies? No,” said Turner, who has never used echinacea. “There’s an almost infinite number of possibilities for these things, but at some point you’ve got to say, ‘Enough is enough.’ ”

That time has passed, said Dr. Wallace Sampson, editor of the Scientific Review of Alternative Medicine and an emeritus adjunct professor of medicine at Stanford University School of Medicine.

In a commentary accompanying the study, Sampson said the scientific community should consider the echinacea question settled and invest its research efforts in “treatments with histories that indicate some reasonable chance of efficacy.”