|
From Capital Health (Predy) and the Department of Agricultural, Food and Nutritional Science, University of Alberta (Goel, Lovlin, Basu), Edmonton, Alta., and the Department of Epidemiology and Biostatistics, University of Western Ontario, London, Ont. (Donner, Stitt)
Correspondence to: Dr. Tapan K. Basu, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton AB T6G 2P5; fax 780 492-4265; tapan.basu{at}ualberta.ca
Background: Upper respiratory tract infections are a major source of morbidity throughout the world. Extracts of the root of North American ginseng (Panax quinquefolium) have been found to have the potential to modulate both natural and acquired immune responses. We sought to examine the efficacy of an extract of North American ginseng root in preventing colds.
Methods: We conducted a randomized, double-blind, placebo-controlled study at the onset of the influenza season. A total of 323 subjects 1865 years of age with a history of at least 2 colds in the previous year were recruited from the general population in Edmonton, Alberta. The participants were instructed to take 2 capsules per day of either the North American ginseng extract or a placebo for a period of 4 months. The primary outcome measure was the number of Jackson-verified colds. Secondary variables measured included symptom severity, total number of days of symptoms and duration of all colds. Cold symptoms were scored by subjects using a 4-point scale.
Results: Subjects who did not start treatment were excluded from the analysis (23 in the ginseng group and 21 in the placebo group), leaving 130 in the ginseng group and 149 in the placebo group. The mean number of colds per person was lower in the ginseng group than in the placebo group (0.68 [standard deviation (SD) 0.82] v. 0.93 [SD 0.91], difference 0.25%, 95% confidence interval [CI] 0.040.45). The proportion of subjects with 2 or more Jackson-verified colds during the 4-month period (10.0% v. 22.8%, 12.8% difference, 95% CI 4.321.3) was significantly lower in the ginseng group than in the placebo group, as were the total symptom score (77.5 [SD 84.6] v. 112.3 [SD 102.5], difference 1.5%, 95% CI 1.22.0) and the total number of days cold symptoms were reported (10.8 [SD 9.7] v. 16.5 [SD 13.8] days, difference 1.6%, 95% CI 1.32.0) for all colds.
Interpretation: Ingestion of a poly-furanosyl-pyranosyl-sacchariderich extract of the roots of North American ginseng in a moderate dose over 4 months reduced the mean number of colds per person, the proportion of subjects who experienced 2 or more colds, the severity of symptoms and the number of days cold symptoms were reported.
Related Article
This article has been cited by other articles:
![]() |
J. K. Seida, T. Durec, and S. Kuhle North American (Panax quinquefolius) and Asian Ginseng (Panax ginseng) Preparations for Prevention of the Common Cold in Healthy Adults: A Systematic Review Evid. Based Complement. Altern. Med., July 10, 2009; (2009) nep068v1. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. P. Li, X. J. Zhao, and J. Y. Wang Synergy of Astragalus polysaccharides and probiotics (Lactobacillus and Bacillus cereus) on immunity and intestinal microbiota in chicks Poult. Sci., March 1, 2009; 88(3): 519 - 525. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Jin, V. S. Kotakadi, L. Ying, A. B. Hofseth, X. Cui, P. A. Wood, A. Windust, L. E. Matesic, E. A. Pena, C. Chiuzan, et al. American ginseng suppresses inflammation and DNA damage associated with mouse colitis Carcinogenesis, December 1, 2008; 29(12): 2351 - 2359. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Vohra, B. C. Johnston, K. L. Laycock, W. K. Midodzi, I. Dhunnoo, E. Harris, and L. Baydala Safety and Tolerability of North American Ginseng Extract in the Treatment of Pediatric Upper Respiratory Tract Infection: A Phase II Randomized, Controlled Trial of 2 Dosing Schedules Pediatrics, August 1, 2008; 122(2): e402 - e410. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Worrall Common cold Can Fam Physician, October 1, 2007; 53(10): 1735 - 1736. [Full Text] [PDF] |
||||
![]() |
J. M. Howard Ginseng enhances the effectiveness of DHEA. Can. Med. Assoc. J., April 11, 2006; 174(8): 1134 - 1134. [Full Text] [PDF] |
||||
![]() |
R. B. Turner Studies of "natural" remedies for the common cold: pitfalls and pratfalls Can. Med. Assoc. J., October 25, 2005; 173(9): 1051 - 1052. [Full Text] [PDF] |
||||
Read all eLetters