Not sure about this exact study, but studies like this usually ignore confounding factors that cause people to abstain. The headline leads people to think that

Not sure about this exact study, but studies like this usually ignore confounding factors that cause people to abstain. The headline leads people to think that they should drink a bit to achieve the result, but that’s usually never the case. For example there were a bunch of studies about how sleeping 10 hours per night has lower mortality rate than sleeping 12+ hours (oh no - are you sleeping too much?!?), but upon further review they realized that people who are really sick or alcoholics are more likely to sleep 12+ hours per night. In this case, wouldn’t be surprised if there are reasons people fit into the zero drink category (health issues) that are associated with cognitive decline.