Drinking green tea and coffee decreases the risk of death for stroke and heart attack survivors

Stroke and heart attack survivors can reduce multiple causes of death and prevent future cardiovascular events by drinking green tea, according to new research published today in Leakage, a newspaper of the American Stroke Association, a division of the American Heart Association. The study also found that daily coffee consumption helps heart attack survivors by reducing the risk of death after a heart attack and can prevent heart attacks or strokes in healthy individuals.

Previous research has examined the health benefits of green tea and coffee in people with no history of cardiovascular disease or cancer. Researchers in the study “Consumption of green tea and coffee and all-cause mortality among people with and without stroke or myocardial infarction” sought to determine the effects of drinking green tea and coffee after surviving a stroke or heart attack.

“There is a great need for scientific evidence on lifestyles among stroke and heart attack survivors, considering the rapidly aging population and the need to improve life expectancy after these cardiovascular events,” said Hiroyasu Iso, MD, professor of public health at Osaka University in Suita, Japan, and the corresponding author of the study.

The researchers analyzed data from more than 46,000 participants (ages 40 to 79, 60% women) from the Japan Collaborative Cohort Study for Cancer Risk Assessment (JACC study), a study conducted in 45 communities in Japan. Participants were invited to complete self-administered questionnaires that included information on demographics, lifestyle, medical history and diet. The people were then divided into three groups: history of stroke; hx of myocardial infarction (MI); and no history of stroke or MI. The researchers then analyzed the amount and frequency of consumption of green tea and coffee. The researchers noted that a typical cup of green tea contains approximately 100mL (about 3.4 ounces) of liquid, and a typical cup of coffee contains approximately 150mL (about 5 ounces) of liquid.

The results include:

When compared to participants who rarely drank green tea, stroke survivors who consumed at least seven cups of green tea a day reduced the risk of all-cause mortality by approximately 62%. The researchers did not observe a statistically significant association between participants without a history of stroke or heart attack.

Heart attack survivors who drank a cup of coffee a day reduced their overall risk of death by approximately 22% when compared to those who did not drink coffee regularly.

People without a history of stroke or heart attack who consumed one or more cups of coffee a week were at approximately 14% lower risk of all-cause mortality compared to those who did not drink coffee.

The consumption of green tea can prevent future cardiovascular events in survivors, while drinking coffee can prevent such events in healthy individuals.

“An important distinction to make is that in Japanese culture, green tea is usually prepared with water and without sugar. In addition, coffee is prepared with water and occasionally milk and sugar,” said Iso. “The healthiest way to prepare these drinks is without an unnecessary amount of added sugar. “

The researchers note that this study was observational, and the reason why drinking green tea and coffee reduced the risk of heart attack and stroke cannot be determined. Further research is needed to understand the details of the different effects of green tea and coffee.