November 10, 2005 – Ginseng may protect against infections of the respiratory system. At least that’s what the results of a test indicate.1 recently published in the journal of the Canadian Medical Association.
Canadian researchers at the University of Alberta and the University of Western Ontario conducted a study of 270 people prone to colds. The trial took place in the Canadian province of Alberta, Edmonton and surrounding areas, during the winter (November to March), a season prone to infections of the respiratory system. Each morning after breakfast, subjects took, for four months, 400 mg of standardized extract of Canadian ginseng (Panax quinquefolius) or a placebo.
Participants who took ginseng had fewer colds than those who took a placebo, according to the results of the study. Once victims of this condition, they presented less intense symptoms than the subjects in the placebo group. Researchers have also observed that ginseng has the effect of reducing the duration of cold symptoms.
The authors of the study estimate that this ginseng extract, rich in poly-furanosylpyranosyl-saccharides, reduces the risk of contracting a respiratory tract infection by 12.8%, the intensity of cold symptoms by 31% and 34 , 5% the number of days during which symptoms appear. They point out that these results are comparable to those obtained in the context of trials conducted with conventional antivirals such as rimantadine, amantadine, zanamivir or oseltamivir.
It is still unclear how ginseng can help fight respiratory tract infections. The authors of the trial believe that it would have an effect on immune functions.
Note that the manufacturer of the supplement, used in this trial, made a financial contribution to the study. Two of the six researchers who conducted this study are even employed by this firm and another acts as a consultant.
Pierre Lefrançois – PasseportSanté.net
According to Foodnavigator.com, BBC.
1. Predy GN, Goel V, Lovlin R, et al. Efficacy of an extract of North American ginseng containing poly-furanosyl-pyranosyl-saccharides for preventing upper respiratory tract infections: a randomized controlled trial.CMAJ. 2005 Oct 25; 173 (9): 1043-8. Full Text [Consulté le 31 octobre 2005] : www.cmaj.ca