A new study has found that consuming eight or more alcoholic drinks per week is associated with signs of brain injury, including damage to small blood vessels and markers related to memory and thinking problems
The research published on April 9, 2025, in Neurology, the medical journal of the American Academy of Neurology, adds to growing evidence that heavy alcohol use can negatively affect brain health, especially as people age.
The effect of alcohol on the brain
Researchers focused on hyaline arteriolosclerosis, which causes small blood vessels in the brain to become thick and narrow.
This reduces blood flow and can lead to lesions, areas of damaged tissue, in the brain. These lesions are linked to problems with memory and thinking.
The study involved 1,781 participants with an average age of 75 at the time of death. All participants underwent brain autopsies. Scientists examined their brain tissue for various signs of damage, including vascular lesions and tau tangles, a protein linked to Alzheimer’s disease.
Researchers also measured brain weight and collected information about participants’ alcohol consumption, reported by family members.
Brain mass and cognitive performance
Based on drinking habits, participants were divided into four groups: people who never drank, moderate drinkers (seven or fewer drinks per week), heavy drinkers (eight or more drinks per week), and former heavy drinkers who had stopped drinking.
Among those who never drank alcohol, 40% showed signs of vascular brain lesions. In comparison, the rate was 45% for moderate drinkers, 44% for heavy drinkers, and 50% for former heavy drinkers. Even after adjusting for other factors that could influence brain health, such as age, smoking history, and physical activity, the odds of having vascular brain lesions were significantly higher in drinkers.
Heavy drinkers had 133% higher odds of having these brain lesions compared to people who never drank. Former heavy drinkers had 89% higher odds, and even moderate drinkers showed a 60% increase in risk. The study also found that both heavy and former heavy drinkers had a higher likelihood of developing tau tangles, a sign often associated with Alzheimer’s disease.
Alcohol toll on life expectancy
Former heavy drinkers were also found to have a lower brain mass ratio, the proportion of brain weight to body size, which may be another indicator of long-term brain changes. This group also showed worse cognitive performance, although no significant cognitive decline was found in current moderate or heavy drinkers at the time of death.
Another striking finding was that heavy drinkers tended to die an average of 13 years earlier than those who never drank.
While the study does not prove that heavy drinking directly causes brain damage, it strongly suggests a link between long-term alcohol use and signs of brain injury. The researchers note that one limitation of the study was the lack of information on how long participants drank or details about their cognitive abilities while alive.
