Scientists from the U.S. National Institutes of Health used nuclear magnetic resonance imaging to study influenza viruses and found that the lipid substances surrounding the virus harden in cold weather, thereby protecting the virus. Scientists believe this may explain why winter is the peak season for influenza.
When influenza begins to spread, vaccination may no longer be ideal. Therefore, other daily preventive measures (such as frequent ventilation, hand washing, taking Banlangen, etc.) should be considered. Japanese researchers suggest that black tea gargling can help prevent influenza and is worth a try.
Professor Shimamura from Showa University School of Medicine conducted an experiment involving 300 students divided into two groups: one group gargled with black tea twice a day, while the other did not. After five months, researchers found that the gargling group was largely unaffected by respiratory viruses such as influenza.
Analysis shows that catechins in black tea are antioxidants that inhibit free radical activity in the body, helping to fend off external viruses and prevent them from infecting human cells. Not only black tea, but green tea has similar effects, though black tea is superior. Moreover, the higher the quality of the tea leaves, the better the preventive effect; low-quality tea has little to no effect.
Professor Shimamura emphasizes that the method of gargling is important for effectiveness. Gargle once after getting up in the morning and once after returning home. Specifically, hold 5% black tea in the mouth for 20 seconds, then spit it out, repeating 2 to 3 times. In addition to gargling, drinking black tea in winter can enhance the preventive effect.