Drinking more than five cups of green tea a day could reduce deaths from cardiovascular diseases, such as cerebral brain infarction, and lead to a longer life, according to a paper by a Tohoku University research team released Wednesday.
The paper by the research team, led by Shinichi Kuriyama, an assistant professor at Tohoku University, was published in the Journal of the American Medical Association. However, the drink’s effectiveness against cancer was not confirmed in the study.
The team followed 40,530 people in Miyagi Prefecture–19,060 men and 21,470 women–over an 11-year period beginning in 1995. The subjects, who were divided into four groups based on how much tea they drank every day, were between the ages of 40 and 79 in 1994.
The death rate among the group that drank more than five cups was 12 percentage points lower in men and 23 percentage points lower in women compared with the group that drank just one cup of tea or less every day.
In particular, the fatality rate for cerebral brain infarction caused by hardened arteries in those people who drank five cups of tea or more was 42 percentage points lower in men and 62 percentage points lower in women than those who drank fewer. The team considers the difference in fatalities between males and females depends on whether they smoked or not.
Although earlier animal testing proved that catechin contained in green tea prevents cardiovascular disease and cancer, the latest study was the first on such a large sample group.
“We couldn’t confirm the preventative effectiveness against death from cancer through this research, but it appears that drinking green tea tends to lead to a longer life,” Kuriyama said.
(By The Yomiuri Shimbun, Sept 2006)
Article URL: http://www.yomiuri.co.jp/dy/features/science/20060915TDY03003.htm