It’s an American ritual — a glass of beer or wine after a long day. For some of us, it might be a couple of glasses of a favorite adult beverage, depending on the day’s stress levels.

But that alcohol consumption — even as little as half a beer a day — might have consequences for your brain.

A team led by scientists at the University of Pennsylvania combed through detailed data on 36,000 people, including MRI scans, and found that even a small daily consumption of alcohol is associated with a reduction in brain size.

That change mimics the effects of aging, suggesting that drinking might lead to premature brain aging and cognitive decline.

The research found, for example, that one to two drinks a day were associated with an alteration of the brain that is the equivalent of two years of aging.

Brain volume fell, the study found, even among those people who quaffed just a couple drinks a week. The biggest drop in brain size, however, is reserved for the heaviest drinkers.

There is much previous research on the impact of alcohol on cognition, including some suggesting moderate consumption had no impact to others saying there might be a benefit.

But the authors of the current investigation say their new study boasts the power of large numbers of participants. Researchers tapped data from the   United Kingdom’s Biobank. This is a massive repository of medical and lifestyle information on legions of people.

Researchers stop short of telling folks to halt their alcohol intake. They do note, however, that the heaviest drinkers are most at risk. Remember: moderation in all things.