Green tea may reduce risk of some cancers
People who drink five cups of green tea each day may be less likely to develop some types of blood cancer, Japanese scientists have suggested.
Researchers at Tohoku University School of Medicine in Sendai carried out a study involving 40,000 Japanese people over a period of nearly ten years.
They found that a high intake of green tea was associated with a lower risk of blood and lymph system cancers.
People who drank at least five cups a day appeared to benefit from a 42 per cent reduced risk of blood cancers compared with those who drank one cup or less.
They also had a 48 per cent lower likelihood of developing cancers of the lymph system, which is part of the body's immune system.
Dr Toru Naganuma, whose team's findings are published in the American Journal of Epidemiology, said that the drink may have a protective effect against "particular cancers".
Green tea is known to contain high levels of antioxidants, and some scientists believe that they may be the reason for the protective effect.
However, the scientific evidence in favour of increasing intake of antioxidants to protect against cancer is inconclusive, and some studies even suggest this may actually dampen the body's ability to fight disease, or even increase cancer risk.
Commenting on the latest study, Yinka Ebo, Cancer Research UK's health information officer, said: "More research is needed to confirm if there is a link between green tea consumption and reduced risk of blood cancers and to find out if this could be relevant to UK adults.
"Years of research have shown that people who eat a healthy, balanced diet, high in fruit, vegetables and fibre and low in red and processed meat, saturated fat, salt and alcohol have a lower risk of cancer.
"There is currently no such evidence for a protective effect of any individual food or drink."
Naganuma, T., Kuriyama, S., Kakizaki, M., Sone, T., Nakaya, N., Ohmori-Matsuda, K., Hozawa, A., Nishino, Y., & Tsuji, I. (2009). Green Tea Consumption and Hematologic Malignancies in Japan: The Ohsaki Study American Journal of Epidemiology, 170 (6), 730-738 DOI: 10.1093/aje/kwp187