According to the results of a new study, even moderate alcohol consumption may significantly reduce brain blood flow, especially in older adults. The research study, published in the journal Alcohol, included 45 healthy participants between the ages of 22 and 70 years who did not have a history of alcohol use disorder (AUD).

As part of the study, participants’ lifetime alcohol use was evaluated and screened for factors affecting brain health. Moreover, the researchers used MRI brain scans to measure participants’ cortical thickness, brain volume, and blood flow. They found that even moderate alcohol consumption was linked to reduced brain blood flow, particularly in those with higher monthly alcohol intake. In addition, this decrease in blood flow, especially in the frontal and temporal lobes of the brain, may impair thinking, memory, and language, potentially contributing to cognitive decline over time.

The researchers also observed that the effects of alcohol on brain blood flow were stronger in older adults, with higher lifetime intake associated with reduced blood perfusion across most brain regions and thinner cortical layers. They suggested that oxidative stress, which damages cells and is linked to aging and inflammation, may be causing these changes, potentially increasing the risk of cognitive decline or dementia.

“For many years, the public message was that light or moderate drinking may be harmless, or even beneficial in some cases,” said Dr. Dung Trinh, internist of MemorialCare Medical Group and Chief Medical Officer of Healthy Brain Clinic, in his interview with Medical News Today. “This study challenges that older idea by suggesting that even alcohol intake within traditional ‘low-risk’ ranges may be associated with measurable brain changes.”

The study’s lead author Timothy Durazzo, professor at Stanford, said that the next phase of the research will examine how low-level alcohol consumption affects balance, coordination, and dexterity in a larger participant group. He also emphasized that the current study’s small sample size, especially for blood flow measures, needs to be confirmed with a larger number of study participants as part of future research.