Recent studies published in the journal of the American Heart Association show that coffee and green tea may reduce the risk of stroke. The study, conducted on a sample of 83,269 Japanese adults, shows that green tea and coffee may lower the risk of stroke by about 30%. This is the first large-scale study to evaluate the combined effects of coffee and green tea on stroke community.
Study participants were followed for a period of 13 years and it was found that the more they drank green tea and coffee, the risk of stroke was lower. The study showed that those who drank one cup of coffee per day had a risk of stroke by 20% lower than those who rarely drank coffee; also those who drank at least one cup of coffee a day and those who drank two cups of green tea had a 32% lower risk of hemorrhagic stroke.
It is not known exactly how green tea protects against stroke, but it seems that catechins are responsible for this due to their antioxidant and anti-inflammatory effects. As for coffee, it seems that it indirectly decreases the risk of stroke by chlorogenic acid ( a compund found in coffee), which prevents the diabetes onset.