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Men may face memory decline if they have more than 2.5 drinks per day

Drinking daily may put middle-age men at risk for memory loss.

New research finds men who imbibed more than 2.5 alcoholic beverages per day experienced memory loss and other cognitive declines up to six years earlier than moderate drinkers or teetotalers.    

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The findings could spell trouble for millions of Americans. The Centers for Disease Control and Prevention recently reported 38 million Americans are heavy drinkers, facing increased risk for chronic diseases such as cirrhosis of the liver, pancreatitis, high blood pressure, mental health disorders and cancers.

“In addition to chronic diseases, alcohol may affect aging outcomes, but this effect remains poorly understood,” wrote the researchers led by Dr. Séverine Sabia, an aging and well-being researcher in the department of epidemiology and public health at the University College London in the U.K.

The study was published Jan. 15 in Neurology.

Researchers looked at more than 5,000 men and nearly 2,100 women for the 10-year study. The participants were asked three times to report their drinking habits. Then, when they were an average age of 56, they underwent tests looking at memory and executive function -- which is the ability to coordinate cognitive skills for daily processes like organization, time management, reasoning and problem solving.

They repeated the test twice over the 10-year period.

Heavy-drinking men showed faster declines in memory and executive function compared to those who drank less. Specifically, their decline was between 1.5 and 6 years earlier than those who drank moderately (one or two drinks per day) or didn't drink at all. The associations were not driven by a particular type of alcohol.

There was no difference in executive function and memory scores between light or moderate drinkers and men who didn’t drink at all.

In women, interestingly, there was only “weak evidence” that heavy drinking was associated with faster declines in executive function. Women who abstained from alcohol entirely, however, showed faster declines in cognitive function, but the authors said the number of abstainers was small and other factors may be at play.

Men who didn’t drink did not show declines in executive function and memory.

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The authors conceded the study had limitations, including that drinking rates were self-reported, and may have been underestimated. They also did not have data on the number of drinks consumed in a sitting, and couldn’t tell if binge drinking or regular heavy drinking would have led to different outcomes.

Previous studies have suggested drinking one or two drinks a day may even protect against dementia and memory decline.

“Our findings are in agreement with previous studies showing that moderate alcohol consumption is probably not deleterious for cognitive outcomes, but they also show that heavy alcohol consumption in midlife is likely to be harmful for cognitive aging, at least in men,” the authors concluded.

Dr. Alison Cook, director of external affairs at the British nonprofit Alzheimer’s Society, said in a statement that a brain that ages faster is at greater risk for dementia.

'We've known for some time that drinking excessive amounts of alcohol is bad for your brain,” said Cook, who was not involved in the study. “Previous research has also shown that by keeping your heart as healthy as possible, you can also protect your brain, so it's important to exercise and eat a healthy diet.”