The leaves of Japanese green tea provide an effective natural remedy for hangovers, medical experts in Japan say. Researchers at Tokyo's Nihon University have identified a substance in the tea, saponin, that decreases the alcohol in the bloodstream of drunken rats.

"In tests rats which drank a saponin extract bfore alcohol absorption showed 30 to 70 per cent lower alcohol levels," Professor Shojiro Tsukamoto of the university's medical faculty, said.

Tsukamoto warns that drinking a few cups of green tea before going to the pub will not prevent inebriation. To be effective saponin, which is already extracted from tea seeds for use as a lather agent in detergents, must be taken in a highly concentrated form.

He says that the effect of green tea in curing hangovers was first noted by Eisai, a writer in 14th century Japan. "We now have the scientific means to produce a very effective remedy, but we will conduct more tests into the side-effects before putting it on the market" he adds.

Some Japanese regard green tea - introduced from China around the 8th century - as a wonder drug, curing verything from tooth decay to diabetes.

According to researchers at the Aichi Cancer center the bitter substance present in the tea slows down the reproduction of the leukaemia virus and the HIV virus that causes AIDS.

Unlike black tea, which loses a large part of its health benefits during its fermentation process, green tea retains its beneficial effects if it is not brewed for too long. - Daily Telegraph.