green teaMany people take coffee or tea breaks throughout the day, and that simple act may help them reduce their risk for stroke, Japanese researchers report.

This study of about 83 000 people suggests that drinking green tea or coffee daily might lower stroke risk by about 20%, with even more protection against a specific type of stroke.

“The regular action of daily drinking [of] green tea and coffee is a benefit in preventing stroke,” said lead researcher Dr Yoshihiro Kokubo, chief doctor in the department of preventive cardiology at the National Cerebral and Cardiovascular Center, in Osaka.

“If you cannot readily improve your lifestyle, try to prevent stroke by drinking green tea every day,” he said.

The link between coffee and tea

Although it isn’t certain why coffee and tea may have this effect, Kokubo thinks it might be due to certain properties in these drinks that keep blood from clotting.

In addition, green tea contains catechins, which have an antioxidant, anti-inflammatory effect. Some chemicals in coffee, such as chlorogenic acid, may cut the risk of stroke by lowering the chances of developing type 2 diabetes, he explained.

Coffee also contains caffeine, which may have an impact on cholesterol levels and blood pressure, and may cause changes in insulin sensitivity, which affects blood sugar, he added.

One expert, Dr Ralph Sacco, past president of the American Heart Association, cautioned that this type of study cannot say for sure that the lower risk of stroke is really the result of drinking coffee or tea.

“Such association studies are still limited in [the] ability to tell whether it is some ingredients in the coffee or tea or some other behavior common to coffee and tea drinkers that is driving the protective effects,” said Sacco, chairman of neurology at the University of Miami Miller School of Medicine.