A recent study published in the journal of the American Academy of Neurology brings new insights into how heavy alcohol consumption affects the brain. The research, conducted on 1,781 participants with an average age of 75 at death, linked regular heavy drinking — defined as eight or more drinks per week — to significant brain injuries, which can lead to memory and thinking problems.
The study focused on identifying markers of brain damage through autopsies, including the presence of hyaline arteriolosclerosis, a condition where small blood vessels become thick and stiff, impeding blood flow and damaging brain tissue. After adjusting for factors such as age at death, smoking and physical activity, heavy drinkers showed a 133% higher likelihood of these vascular lesions compared to non-drinkers. Moreover, even former heavy drinkers still exhibited an 89% higher likelihood, while in moderate drinkers (seven or fewer drinks per week) it was 60% higher.
Researchers also observed that heavy and former heavy drinkers had a greater presence of tau tangles, a biomarker associated with Alzheimer’s disease. Although only former heavy drinkers showed a significant reduction in brain mass and worse cognitive abilities compared to those who never drank, according to the study, this might be due to a lower life expectancy in heavy drinkers.
However, moderate drinking showed no association with brain mass reduction or cognitive decline. The study argues that this might be due to other factors, such as healthier lifestyles, better social engagement, and higher socioeconomic status among moderate drinkers.
This research highlights a critical public health concern: heavy drinkers, on average, died 13 years earlier than non-drinkers. Though the study cannot prove causality, it provides robust evidence linking heavy alcohol consumption to long-term brain injury and impaired cognitive function, mainly associated with damage to small blood vessels in the brain. These findings underline the importance of preventive strategies to reduce heavy drinking.
Coordinator at la Verneda-Sant Martí Learning Community and adjunct professor at the University of Barcelona