A glass of wine or a pint of beer each night increases the risk of stroke

A major study showed that drinking only one or two glasses of alcohol per night significantly increased the risk of having a stroke later in life.

Experts from the University of Oxford said that their study of 500,000 people finally dispelled the "myth" that mild consumption of alcohol protects health.

They found that one or two glasses a day increased the risk of having a stroke by 10 to 15% over the next ten years, and four glasses a day by 35%.

For years, many experts have argued that moderate consumption of alcohol has a protective effect – citing studies showing that rare glasses of wine or pints of beer reduced the risk of heart attack and d? stroke.

Critics argue that these studies were wrong – because they included alcoholics who became adults or people who did not drink because of other health problems.

The evidence therefore suggested that light drinkers were at a lower risk than those who drank nothing at all.

The new study, published in the Lancet medical journal, circumvented this problem using a genetic study of the Chinese population.

A third of the Chinese population has a genetic quirk that means they can not tolerate the drink.

Their genes mean that they do not have the ability to eliminate a toxic byproduct of alcohol – which makes them become nauseous and blush after even a small volume of drink.

The researchers tested the genes of people in ten regions of China and then followed their consumption of alcohol.

Those who did not drink because of their genetic mutation were considered a reliable marker of zero alcohol consumption because they simply could not tolerate the drink.

The other two-thirds of the participants who did not have the same genetic disorder were able to drink freely – and men on average drank four drinks a day and were at a much higher risk of suffering from high blood pressure and stroke.

Chinese women drank very little, regardless of their genetic makeup.

The researcher, Professor Sir Richard Peto, co-director of the Clinical Trials Unit at Oxford University, said he was confident that the results could be even better. apply to British men and women.

"If women drink like men, they die like men," he said.

He pointed out that the conclusions were not meant to dissuade people from drinking – and said that smoking would have a much greater impact on risk.

Sir Richard said, "I do not think people will change what they drink because of these results.

"But we have the truth about a story that's been a myth for centuries." Professor Zhengming Chen, also head of the Oxford study, said, "It has been argued that moderate consumption of alcohol can be beneficial, especially for cardiovascular disease.

"This study shows very solid evidence that refutes this claim. The key message is that this protective effect is not real.

"Even a moderate consumption of alcohol increases the chances of having a stroke." He added: "The results of the heart attack were less well defined, so we plan to collect more evidence." The study supports the official guidelines on alcohol consumption published by Chief Medical Officer, Sally Davies, in 2016, who warned that there is no level of consumption " safe".

Prominent scientists who initially criticized these guidelines said that they could change their minds in the light of new discoveries.

David Spiegelhalter, professor in charge of the public's understanding of risk at the University of Cambridge, said: "I've always been reasonably confident that moderate consumption of alcohol protects against diseases. cardiovascular, but I now have doubts. "

He added, "This is a very impressive study that shows that men who, by chance, possess a combination of genes that dissuade them from drinking alcohol, have a risk of Stroke less than those who do not have one.

"The fact that this is not true for Chinese women, who tend not to drink whatever their genes, suggests that this effect is due to alcohol rather than to the genes themselves." . He added: "The increase in the total risk of stroke was about 38% for 40 g of alcohol consumed per day; this is five British units, or more than half a bottle of wine.

"To give you an idea, it's very roughly the opposite effect of taking a statin."