Drinking several cups of green tea each day may substantially reduce a person’s risk of cardiovascular disease, a study of more than 40,000 people in Japan has found. But the new findings also cast doubt on the prevalent idea that the drink offers protection against cancer.

  Researchers began the study in1994 by asking participants in north-east Japan how much green tea they consumed each day. About a quarter of the 40,000 subjects drank less than one cup a day, on average, while a similar number reported drinking more than five cups, or half a liter, daily.

  The team, led by Shinichi Kuriyama of the Yohoko University Graduate School of Medicine in Sendai, Japan, then tracked the health of the participants for more than a decade. The number of participants who died from cardiovascular causes during this period was small-less than 1% of those in each category of tea consumption.

  Controlling for lifestyle factors, those who consumed more than five cups of green tea daily had a 26% lower risk of dying from cardiovascular disease than those who consumed less than one cap per day.

  Previous research had suggested that green tea reduces the risk of heart disease, but Kuriyama and colleagues say their large-scale study adds strong support.