Moderate alcohol consumption may lead to slower mental decline in middle-age and older people, a new study found.
Some previous studies have suggested that moderate drinking has beneficial cognitive effects; others have found it harmful.
In the new study, published in JAMA Network Open, researchers tracked the cognitive abilities of almost 20,000 people for an average of more than nine years. The scientists tested the participants in three domains: mental status, word recall and vocabulary.
In all three areas, compared with abstaining, low to moderate drinking (eight drinks a week or fewer for women, and 15 or fewer for men) was associated with a higher mental functioning trajectory and significantly slower decline over the years. Even former drinkers showed slower mental decline than people who never drank.
The study adjusted for smoking, marital status, education, chronic disease and body mass index, but the authors acknowledged that it was an observational study so it could not prove cause and effect. They also noted it relied on self-reports of alcohol consumption, which can be unreliable.
“Drinking should be limited to moderate levels,” said the lead author, Ruiyuan Zhang, a doctoral student at the University of Georgia. “Heavy drinking makes cognitive function worse.”
He added: “If you are not drinking now, there is no reason to start drinking to preserve cognitive function. There are many other ways to prevent cognitive decline — exercise, reading and so on.”