Scientists said cutting back on the last drink of the evening could improve brain health.
The study found that the negative effects of alcohol consumption grow stronger with each additional drink. If you reduce your drinking, you could potentially have the most to gain.
The study's first author, who is based at the University of Wisconsin-Madison, said there is some evidence that drinking can have an effect on the brain. That means that cutting back on that last drink of the night might have a big effect on brain aging.
The study found that people who drank the most had a smaller brain and less white matter in it. Even modest levels of drinking a few glasses of wine a week appeared to carry a risk. The link between alcohol consumption and reductions in brain volume grew stronger the higher the level of alcohol consumption.
Previous research has shown a link between alcohol consumption and brain health. It was not clear if moderate levels of drinking had an impact. The National Health Service recommends not to drink more than 14 units a week on a regular basis.
The study used a large amount of scans from the UK Biobank to examine the relationship between drinking and brain health.
The link between alcohol consumption and brain volume grew stronger as the level of alcohol consumption increased.
In 50-year-olds, increasing average drinking from one alcohol unit to two units was associated with changes in the brain equivalent to aging two years. It took three and a half years to go from two to three alcohol units at the same age.
The more you drink, the worse it gets.
The study shows an association between drinking and brain volume.
There are plausible reasons for believing that alcohol has a negative impact on the brain. Alcohol intoxication could cause the loss of grey matter and the structure of white matter connection in the brain, according to Wetherill.
In the future, the authors hope to look in more detail at drinking patterns, such as whether drinking one beer a day is better than drinking none during the week and then seven on the weekend.
The findings are published in a journal.