Light or moderate drinking may lessen the risk of one type of stroke but not another, while heavy drinking rises the risk of both types, a new study suggests.
A research team from England and Sweden reviewed 25 studies as well as national statistics from Sweden.
The investigators reported that consumption of up to two drinks a day was linked to a lower risk of ischemic stroke (blocked blood flow to the brain), but seemed to have no effect on the risk of bleeding (hemorrhagic) stroke.
According to the American Stroke Association, about 87 percent of strokes are ischemic strokes, while the other 13 percent are hemorrhagic.
High-to-heavy drinking (two to more than four drinks a day) was linked to an added risk of both types of stroke, according to the findings published online last week in the journal BMC Medicine.
The differences between alcohol consumption and type of stroke may be due to the way alcohol affects the body, the study authors noted.
Although the researchers found an association between alcohol and stroke risk, the study does not prove cause and effect. The researchers said factors other than alcohol use may have affected the results.