Healthnotes Newswire (November 9, 2006)—Seniors can boost the effect of the flu vaccine by gargling with a green tea extract, suggest new findings.

The flu (short for influenza) is caused by a virus. Health officials try to anticipate the strain of flu virus that will be the most likely to strike each year and create vaccines to help prevent infection. Most people can get the vaccine if supply is adequate, but it is especially recommended for elderly people because they are more vulnerable to complications.

There are many other ways to stimulate the immune system and possibly prevent colds and flus. Some people use echinacea (Echinacia purpurea), an herb that increases immune cell numbers to fight off infection; others swear by vitamin C. In one study, simply gargling with tap water three times per day was found to decrease the incidence of upper respiratory infections.

A new study of flu prevention, published in the Journal of Alternative and Complementary Medicine, took place in a nursing home, where 124 people 65 years or older were vaccinated against the flu and then began gargling three times per day for three months. Of them, 76 gargled with a green tea extract containing 200 mcg of catechins (the major antioxidant in green tea) per milliliter, while the remaining 48 gargled with water.

Compared with the water gargling group, in which five people (10%) came down with the flu, only one person (1.3%) who gargled with the green tea extract contracted the flu during the study.

Green tea catechins are known for their antioxidant properties and their ability to help the liver clear toxins from the body. Catechins might also protect against cancer. The people who participated in the current study probably benefited from catechins’ antiviral and immune-strengthening properties.

“These results suggest a clear benefit to older vaccinated people from gargling with green tea,” commented Linda Dacey, MD, an internist who treats many people with the flu every winter. She added, “If randomized trials bear out these findings, a combined approach of vaccination and green tea gargles could make a difference in how we help older people avoid the flu and its dangerous consequences.”

The gargle’s concentration of catechins was equivalent to a weak cup of brewed green tea. People who want to increase their chance of avoiding the flu can safely and inexpensively add daily green tea gargling to their immune system–supporting regimens.

(J Altern Complement Med 2006;12:669–72)