Even just one or two alcoholic drinks a day could increase the likelihood of having a stroke, according to a new study published Thursday.
Prior research has frequently suggested that consumption of small amounts of alcohol can offer health benefits and actually prevent disease. But the new study, along with one published last year that there is no amount of drinking with an overall health benefit, suggests this may not be the case, according to CNN.
The new study was published in the journal The Lancet. Researchers at Peking University, the Chinese Academy of Medical Sciences, and the University of Oxford, tracked 500,000 Chinese people over ten years. They found that one or two alcoholic beverages increased risk of stroke between 10 and 15 percent, and that four drinks a day raised the risk 35 percent. A single drink was measured as a glass of wine, bottle of beer, or a shot of liquor.
“There are no protective effects of moderate alcohol intake against stroke. Even moderate alcohol consumption increases the chances of having a stroke,” according to co-author Zhengming Chen, of Oxford University’s Nuffield Department of Population Health. “The findings for heart attack were less clear-cut, so we plan to collect more evidence.”
About one third of East Asians have a genetic variant that leads alcohol to be broken down differently in the body, causing an unpleasant flushing reaction. Those with the variation often drink less. And since anyone can have this reaction regardless of other health or social factors, the researchers were able to track the risk of stroke separately from these other factors.
In women, only 2 percent drank most weeks compared to 33 percent of men. This also allowed researchers to conclude that the alcohol consumption itself is increasing stroke risk. This also suggested that past studies that have shown higher risk at low rather than moderate consumption may have been showing the effects of other health factors that drove people to drink less.
University of Cambridge’s David Spiegelhalter, Winton professor for the public understanding of risk, said he found the study convincing:
“The fact that this is not true for Chinese women, who tend not to drink whatever their genes, suggests this effect is due to the alcohol rather than the genes themselves. I have always been reasonably convinced that moderate alcohol consumption was protective for cardiovascular disease, but now I am having my doubts.”