One of the oldest and most storied herbal remedies around is ginseng. It is one of the top natural remedies you can use to boost your immune system and prevent disease.
Ginseng extracts enhance immune responses by stimulating immunoglobulin production by lymphocytes as well as increasing the activity of lymphokine-mediated killer cells. Moreover, ginseng extracts can stimulate the cell-mediated immune response. Of the many medicinal fractions from ginseng root, the immunologic activity is primarily due to polysaccharides and less from ginseosides.
There are several clinical studies that demonstrate the beneficial effects of ginseng extracts in acute respiratory disease.
In two randomized, double-blind, placebo-controlled trials conducted in 2000 (eight weeks) and 2000-2001 (12 weeks) during the influenza season, 89 (2000) and 109 (2000-2001) elderly patients in either nursing homes or assisted living setting were given a ginseng extract (200 mg a day) or placebo to prevent acute respiratory illness in institutionalized older adults. Results showed that the ginseng-treated group experienced an overall 89% reduction in risk of acute respiratory infections.
In a Canadian study, 323 subjects between aged 18-65 years old with a history of at least two colds the previous years were given two ginseng capsules a day or placebo for a period of four months. Results showed that ginseng reduced the mean number of colds per persons, the number of individuals who previously experienced two or more colds, the severity of symptoms, and the number of days of cold symptoms. The authors concluded that the ginseng effects were comparable to commonly prescribed antiviral drugs for influenza.
In a good-quality study, 43 individuals 65 years or older were given “COLD-FX” (a ginseng product) or placebo for four months. Results of this study showed that the ginseng product reduced the risk and duration of respiratory symptoms by 48% and 55%, respectively.