Researchers conducted a study on a total of 83,269 Japanese adults aged 45 to 74 years, they monitored their green tea and coffee consumption for an average of 13 years to see whether it had any effect on cardiovascular health.
The results of the study indicated that there's a link between high consumption of green tea and coffee and a lower stroke risk.
The researchers analyzed the participants' medical records during the 13 years of follow up, they looked for information about whether they experienced strokes or other health complications. Their findings were adjusted for factors such as age, sex, diet, smoking status, and weight.
They found that:
- Those who drank green tea regularly - at least four cups measuring six ounces per day - were about 20 to 30 percent less likely to experience a certain type of stroke compared to those who didn't.
- Daily coffee drinkers were at a 20 percent lower risk of stroke compared to those who rarely drank it.
It should be noted that in general the green tea drinkers did more exercise than the other participants.
Previous research indicates that green tea can lower one's risk of heart disease. A study conducted by researchers at UCLA similarly found that the more green tea you drink, the better your odds of staving off a stroke.
The initial results of the study found that those who drank more than two cups of coffee a day were at a higher risk of developing coronary heart disease (CHD), however, after factoring in cigarette smoking they no longer found an association between coffee consumption and CHD.
In fact, according to a study published in Stroke: Journal of the American Heart Association, women who drink more than one cup of coffee per day appear to have a 22 to 25% lower risk of stroke than those who don't.
"However, our self-reported data may be reasonably accurate, because nationwide annual health screenings produced similar results, and our validation study showed relatively high validity. The regular action of drinking tea, coffee, largely benefits cardiovascular health because it partly keeps blood clots from forming." Possibly catechins and chlorogenic acid reduce stroke risk
According to the lead author, Yoshihiro Kokubo, M.D., Ph.D., F.A.H.A., F.A.C.C., F.E.S.C., lead author of the study at Japan's National Cerebral and Cardiovascular Center:
"This is the first large-scale study to examine the combined effects of both green tea and coffee on stroke risks. You may make a small but positive lifestyle change to help lower the risk of stroke by adding daily green tea to your diet."
The researchers are not completely certain what property is in green tea that lowers stroke risk, although they believe it could be a compound group called catechins which have antioxidant and anti-inflammatory effects.
There's a chemical in coffee called chlorogenic acid which reduces a persons risk of developing type 2 diabetes, this could be why coffee drinkers are at a reduced risk of stroke.
As coffee and green tea are the two most popular drinks in the world after water, the finding is very relevant to the U.S. and western Europe as well. -Joseph Nordqvist
Drinking green tea or coffee on a regular basis is associated with a reduced risk of stroke, says new research published in Stroke: Journal of the American Heart Association.