Even light-to-moderate drinking increases blood pressure and the chances of having a stroke, according to a large genetic study in The Lancet, countering previous claims that one or two drinks a day could be protective.
The UK and Chinese researchers followed 500,000 Chinese people for 10 years.
They say the findings are relevant to all populations and the best evidence yet on the direct effects of alcohol.
Experts said people should limit their alcohol consumption.
It is already known that heavy drinking is harmful to health and increases stroke risk – but some studies have suggested drinking small amounts can be good for the health, while others indicate there is no safe level of alcohol consumption.
What did the research find?
The researchers, from the University of Oxford, Peking University and the Chinese Academy of Medical Sciences, found that:
- drinking one to two alcoholic drinks every day increased stroke risk by 10-15%
- drinking four drinks every day increased the risk of having a stroke by 35%
For the purposes of their study, one drink was defined as either:
- a small glass of wine
- a bottle of beer
- a single measure of spirits
About 16 in 100 men and 20 in 100 women will have a stroke in their lifetime in the UK.
So, if a group of 100 non-drinkers started drinking a glass or two every day, there would be an extra two strokes – a small increase./BBC