Green tea may cut the risk of dying from pneumonia in women

October 29, 2009

Drinking green tea continues to show health benefits, particularly among women according to the results of a new study from Japan . Drinking five or more cups a day cut the risk by "47 percent in Japanese women," but not Japanese men, Ikue Watanabe, from Tohoku University Graduate School of Medicine in Sendai , Japan notes in an interview.

Pneumonia risk seems to be reduced even by drinking small amounts of green tea.

Drinking as little as one cup or less of green tea per day was associated with 41 percent less risk of dying from pneumonia among Japanese women, the investigators found. The findings, they say, "support the possibility" that green tea contains compounds capable of destroying or inhibiting the growth of viruses and microorganisms. Watanabe and colleagues assessed how drinking green tea affected the risk of dying from pneumonia among 19,079 men and 21,493 women receiving National Health Insurance in Japan . The study population ranged from 40 to 79 years old and participants had no reported history of cancer, heart attack, stroke at the start of the study.

Through more than 12 years of follow up in about 85 percent of the study group, 406 study participants died from pneumonia, the investigators report in the American Journal of Clinical Nutrition. They found benefits from drinking green tea in women, but not in men, after allowing for age, physical function, and smoking status, plus numerous other health and dietary factors potentially associated with the risk for pneumonia.

Watanabe speculates that "green tea may have an effect on pneumonia in women in other countries as well." The study is published in the September 2009 issue of the American Journal of Clinical Nutrition.


Green tea may curb risk of lymphoma and leukemia

Drinking green tea may lower your risk of developing certain blood cancers, but it will take about 5 cups a day, according to a study from Japan . Drinking green tea has been associated with a lower risk of dying from numerous causes and dying from heart disease, lead author of the study Dr. Toru Naganuma, at Tohoku University School of Medicine in Sendai , Japan states in an interview. The current study, Naganuma said, suggests drinking green tea may have a favorable effect "for particular cancers."

After gathering information on the diets and green tea drinking habits of 19,749 men and 22,012 women aged 40 to 79 who had no previous history of cancer the researchers followed the group for development of blood (leukemia) and lymph system (lymphoma) cancers. The lymphatic system is the circulatory system used by the immune system. After 9 years of follow up, 157 blood, bone marrow, and lymph system cancers developed in the study group.

Naganuma's team found that the overall risk for blood cancers was 42 percent lower among study participants who drank 5 or more, versus 1 or fewer, cups of green tea daily.

Drinking 5 or more cups of green tea daily was also associated with 48 percent lower risk for lymph system cancers. These associations held up in analyses that allowed for age, gender, education, smoking status and history, alcohol use, and fish and soybean consumption. The researchers also observed a reduced risk for blood-related cancers among obese study participants, who are "considered to have higher risk of these cancers," Naganuma said. The study is published in the September 15 th , 2009 issue of the American Journal of Epidemiology .