1er August 2005 – Authors of a clinical trial1 that has just published the New England Journal of Medicine conclude that echinacea is ineffective in preventing or treating colds. The double-blind trial was conducted in 399 healthy adults who were experimentally transmitted with colds by infecting them with a common rhinovirus. The results indicate that the three extracts tested had no significant effect on the onset of symptoms or on their intensity.
A member of the research team, Rudolf Bauer, professor at the Institute of Pharmacognosy at the University of Graz (Austria) and a world expert in the standardization of echinacea extracts, notes that “to be effective, a echinacea extract should contain alkamides, cichoric acid and polysaccharides ”. However, the extracts used in this test did contain polysaccharides and alkamides, but nothing is said about their cichoric acid content. “In my experience, the negative results obtained during certain clinical trials with echinacea are certainly attributable, at least in part, to the use of preparations or extracts which do not contain the correct blend of active substances”, a- he already declared2. Professor Bauer co-signed a clinical trial last year with a properly standardized extract that showed positive results for the relief of cold symptoms.3.
The dosages used in the trial, the results of which have just been published, may have been insufficient, said Mark Blumenthal, director of the American Botanical Council, an independent organization dedicated to the study of medicinal plants. . The subjects were indeed given the equivalent of 900 mg of echinacea per day, while the normally recommended dose is instead 3 g per day (3000 mg).
According to researcher Timothy Lee, professor of immunology at Dalhousie University School of Medicine, Canada, “the statistical analysis of the trial data is incomplete and biased.” He explains that two of the three extracts tested had a significant protective effect in comparison with the effects of placebo. Although they were infected with the virus, 24% of those treated did not show clinical symptoms of the common cold, and in those who did, the symptoms were 31% less. “I am amazed that the New England Journal of Medicine agreed to publish this article ”, says Pr Lee.
Note that the principal investigator of the team that conducted this trial, Dr Ronald Turner, is a consultant for large pharmaceutical companies that are active in the field of synthetic drugs to treat infections of the respiratory system, including Wyeth and Schering-Plow1.
Pierre Lefrançois – PasseportSanté.net
According to Reuters Health, Canada NewsWire, The Globe and Mail and The sun.
1. Turner RB, Bauer R, et al. An evaluation of Echinacea angustifolia in experimental rhinovirus infections.N Engl J Med. 2005 Jul 28; 353 (4): 341-8.
2. Bauer R. The constituents of Echinacea and their relevance for standardization. Presentation at the First Natural Health Products Research Conference, held in Montreal in 2004 by the Canadian NHP Research Society.
3. Goel V, Lovlin R, et al. Efficacy of a standardized echinacea preparation (Echinilin) for the treatment of the common cold: a randomized, double-blind, placebo-controlled trial.J Clin Pharm Ther. 2004 Feb; 29 (1): 75-83.