Glass of wine a day won’t keep doctor away
Even light drinking raises stroke risk says study that debunks claim abstinence leaves you in danger
THE myth that a drink a day could protect against stroke has been debunked by scientists.
Researchers at the University of Oxford said that alcohol not only did not have a protective effect, but that moderate drinking raised the risk by up to 15 per cent. Previous studies have suggested that one or two glasses of wine or beer a day could lower the risk of stroke by more than 50 per cent, and seemed to show that people who abstained from alcohol were in greater danger than moderate drinkers.
But the scientists said those studies had been skewed by people who had given up alcohol because of underlying health problems. They were at greater risk not because they were not drinking, but because they were already ill.
To get around the problem, the team looked at 160,000 people in China, some of whom carried a genetic mutation that limited the amount of alcohol they could drink because they suffered flushes and heart palpitations.
While previous research has relied on self-reporting, the new study allowed scientists to see for the first time exactly what people were drinking, because they physically could not consume more than a certain amount.
Prof Zhengming Chen, coauthor from the Nuffield Department of Population Health, University of Oxford, said: “It has been claimed that light to moderate drinking is potentially beneficial. We have really robust evidence that refutes those claims.
“There are no protective effects of moderate alcohol intake against stroke. Even moderate alcohol consumption increases the chances of having a stroke. The findings for heart attack were less clear-cut, so we plan to collect more evidence.”
Among the men in the study – published in The Lancet – the genetic variants led to average alcohol intakes from near zero to about four units a day.
About 10,000 had a stroke and 2,000 had a heart attack during about ten years of follow-up. But those who had genetic variants that decreased alcohol intake also had decreased blood pressure and stroke risk, allowing the authors to conclude that alcohol increases the risk of having a stroke by about a third (35 per cent) for every four additional drinks per day. There was no protective effects of light or moderate drinking.
Although the results were unclear for women – because just two per cent of women in China drink on a weekly basis – the researchers said the outcome was likely to be the same. Prof Sir Richard Peto at the University of Oxford said: “We’ve got the truth about a story that has been a myth for ages. This is for the first time we’ve had reliable evidence about the cause and effect relationship.
“We’re not recommending what anyone should do. If people want to keep killing themselves they should keep on killing themselves.”
The authors said it would be impossible to do a similar study in Western populations, where almost nobody has the relevant genetic variants, but say the findings are applicable worldwide.