A new study has suggested that a daily moderate dose of alcohol can reduce the risk of ischemic stroke, but heavy drinking increases the risk of other types of stroke. The researchers reviewed 25 studies and found that two drinks a day reduced the risk of ischemic stroke, but increases the risk of a bleeding stroke.
The American Stroke Association estimates that 87 percent of strokes are ischemic, while 13 percent are bleeding.
On the other hand, heavy drinking – over two drinks a day – was associated with a higher risk of both types of stroke.
Lead author Susanna Larsson explained, “Our results showed that heavy drinkers were about 1.6 times more likely to suffer from intracerebral hemorrhage and 1.8 times more likely to suffer from subarachnoid hemorrhage. The association between heavy alcohol consumption and these two types of stroke was stronger than that for ischemic stroke.”
“Previous research has found an association between alcohol consumption and lower levels of fibrinogen — a protein in the body which helps the formation of blood clots. While this may explain the association between light-to-moderate alcohol consumption and lower ischemic stroke risk, the adverse effect of alcohol consumption on blood pressure — a major risk factor for stroke — may increase the risk of hemorrhagic stroke and outweigh any potential benefit,” Larrson added.
The study did not prove causality, and other factors may also contribute to one’s stroke risk aside from alcohol intake.