醫(yī)療英語：常喝綠茶和咖啡可降中風風險

Green tea and coffee may help lower the risk of stroke, especially when both are taken as a regular part of the diet, according to a research published on Thursday in Stroke: Journal of the American Heart Association.

"This is the first large-scale study to examine the combined effects of both green tea and coffee on stroke risks," said Yoshihiro Kokubo, lead author of the study at Japan's National Cerebral and Cardiovascular Center. "You may make a small but positive lifestyle change to help lower the risk of stroke by adding daily green tea to your diet."

Researchers asked 83,269 Japanese adults about their green tea and coffee drinking habits, following them for an average span of 13 years. They found that the more green tea or coffee people drink, the lower their stroke risks.

People who drank at least one cup of coffee daily had about a 20-percent lower risk of stroke compared to those who rarely drank it. People who drank two to three cups of green tea daily had a 14- percent lower risk of stroke and those who had at least four cups had a 20-percent lower risk, compared to those who rarely drank it.

And people who drank at least one cup of coffee or two cups of green tea daily had a 32-percent lower risk of intracerebral hemorrhage, compared to those who rarely drank either beverage.

Intracerebral hemorrhage happens when a blood vessel bursts and bleeds inside the brain. About 13 percent of strokes are hemorrhagic.

Participants in the study were 45 to 74 years old, almost evenly divided in gender, and were free from cancer and cardiovascular disease. During the 13 years of follow-up, researchers reviewed the participants' hospital medical records and death certificates, collecting data about heart disease, strokes and causes of death. They adjusted their findings to account for age, sex and lifestyle factors like smoking, alcohol, weight, diet and exercise.

Tea and coffee are the most popular drinks in the world after water, which suggests that these results may also apply in America and other countries, the researchers said.

It's unclear how green tea affects stroke risks. A compound group known as catechins may provide some protection, according to the researchers.

Catechins have an antioxidant anti-inflammatory effect, increasing plasma antioxidant capacity and anti-thrombogenic effects.

相關新聞：美國心臟病協(xié)會主辦的期刊《中風》14日刊登論文稱，日本研究人員的調(diào)查顯示常喝綠茶和咖啡的人出現(xiàn)中風的風險更低，如果日常生活中兩種飲品都經(jīng)常飲用，降低中風風險的效果則更佳。

日本國立大腦和心血管中心的研究人員對8萬多名年齡在45歲至74歲的成年人進行了為期13年的隨訪，并記錄他們的飲食習慣。研究開始時，這些人中沒有癌癥或心血管病患者。隨訪期間，研究人員通過分析他們的醫(yī)療記錄，收集心臟病、中風及死因等方面的數(shù)據(jù)。

分析顯示，即使在考慮年齡、性別、生活方式等因素后，常喝綠茶和咖啡也與中風風險下降存在關聯(lián)。與幾乎不喝綠茶或咖啡者相比，每天飲用兩到三杯綠茶者出現(xiàn)中風的風險低14%，每天至少喝一杯咖啡者出現(xiàn)中風的風險低20%。此外，后兩部分人群出現(xiàn)腦溢血的風險也要低32%。

研究人員表示，常飲綠茶或咖啡降低中風風險的原因目前還不清楚，不過綠茶內(nèi)的成分兒茶素具有抗氧化、消炎等功能，咖啡內(nèi)的綠原酸具有抗氧化、抗菌等功能，它們可能發(fā)揮了作用。研究人員認為，茶和咖啡在世界范圍內(nèi)都是很常見的飲品，這意味著它們在降低中風風險方面的好處容易推廣。