Sept. 24, 2002 -- Green tea drinkers may have the edge in fighting the sniffles and runny eyes of allergy season. Researchers say they've found an ingredient in green tea that stops a key process in producing an allergic response and the symptoms that follow.

Laboratory tests show the compound blocks the production of two substances in the body that trigger and sustain allergic reactions (histamine and immunoglobulin E, or IgE). Researchers think the compound, methylated epigallocatechin gallate (EGCG), may have a similar effect in humans.

"Green tea appears to be a promising source for effective anti-allergenic agents," says researcher Hirofumi Tachibana, associate professor of chemistry at Kyushu University in Fukuoka, Japan, in a news release. "If you have allergies, you should consider drinking it."

The study appears in the Oct. 9 issue of the Journal of Agricultural and Food Chemistry.

Other compounds in green tea already have been shown to have anti-allergy properties, but the researchers say methylated EGCG seems to be the most potent identified so far. EGCG is an antioxidant that's found in highest concentrations in green tea, which is the least processed of tea types. It is found in lesser amounts in black and oolong teas.

Researchers say they don't know how much green tea a person would have to drink to get allergy relief. Neither do they know which varieties of green tea might work best.

But they say people have been drinking tea to relieve the sneezing, coughing, and watery eyes associated with allergies and colds for many years even though it has not been proven that the drink has an actual therapeutic effect in humans.

According to the study, green tea is the second-most consumed beverage in the world, behind water. Previous research also has suggested that the popular drink may help fight cancer, heart disease, arthritis, and tooth decay.

Until more studies are done to determine if green tea actually helps people with allergies, researchers recommend allergy sufferers talk with their healthcare provider about treatment options and minimizing exposure to potential allergy triggers.