Prevention of Colds and the Flu with Gargling
Scientific Studies Find Water and Green Tea Gargles Effective
Jan 30, 2009
In a 2005 article, referencing a Japanese study published in the American Journal of Preventive Medicine, gargling with water helped to prevent the common cold by 36%. Many Japanese people practice gargling for the prevention of colds, but the common belief is that gargling with a substance like a diluted iodine mouth rinse or green tea is the main preventer, not merely water.
Western Medical Reponse to Japanese Study
Some Western medical researchers partially discount the validity of this study because the study did not include participants who developed influenza-type symptoms, therefore the prevention percentage may have been lower than if they had. Also, some researchers feel that the placebo effect, when a percentage of participants' positive expectations cause a positive effect, may have influenced the findings since study participants knew that gargling was part of the study.
However, Kazunari Satomura, MD, PhD, from the University of Kyoto in Japan, lead researcher on this 2005 gargling study explained: "I think the results show that in this study the placebo effect plays only a small role, [because] we explained to the participants at the beginning of the study that there is no scientific evidence on the prevention of common colds by gargling.”
Gargling with Green Tea
A similar study on gargling with green tea rather than water, from another Japanese study in 2006, published in the Journal of Alternative and Complementary Medicine, found that the effectiveness of flu vaccine given to the elderly was enhanced by gargling with green tea. The findings seem to point to the immune-strengthening properties of catechins, substances found in green tea, known for their antioxidant properties.
More Scientific Studies Needed
Daily gargling, 2-3 times per day, seems promising as a possible method of preventing contraction of colds and the flu in healthy individuals. More scientific studies are needed to verify these findings, in particular, double-blind studies would be most helpful, a double-blind study is when both the subjects and the researchers do not know who is receiving the treatment being studied.
No one knows exactly what aspect of gargling may work to prevent viruses. Some hypothesize that cleansing of the mouth and throat prevents viruses. Others suggest that the disinfection by chlorine in the water is the primary preventive factor. Some natural health practitioners even have recommended warm water to be more effective than cold, although there is no scientific data to confirm this.
Inexpensive Prevention Tool
James A. Taylor, MD, a medical researcher from the University of Washington says that there is a polarization between alternative medicine and conventional Western medicine, so that there is often not an openness to listening to the other position. He further states that just because a substance is natural, does not mean it is necessarily non-toxic, however gargling with water or green tea should not pose any health risks.
Certainly, this inexpensive, simple health habit should be studied further. Medscape, an informational website for health professionals, concludes “for now, the regular use of gargling seems as legitimate as other more commonly used means to prevent the common cold.”
