Everyone knows that drinking to excess is bad for your health (and potentially embarrassing), but a new study conducted by researchers at the University of Rochester Medical Center (URMC) indicates drinking in moderation can be good for the brain. The study found that low levels of alcohol consumption can reduce inflammation and help flush the brain of toxins, including beta amyloid and tau proteins associated with Alzheimer's disease.
"Prolonged intake of excessive amounts of ethanol is known to have adverse effects on the central nervous system," says Maiken Nedergaard, M.D., D.M.Sc., co-director of the Center for Translational Neuromedicine at URMC and lead author of the study. "However, in this study we have shown for the first time that low doses of alcohol are potentially beneficial to brain health, namely it improves the brain's ability to remove waste."
In the study, the brains of mice exposed to high levels of ethanol over a long period not only exhibited cognitive and motor skill impairment, but also showed high levels of a molecular marker for inflammation. This was particularly evident in astrocytes, which are cells that play a key role in the regulation of the glymphatic system that helps flush waste products from the brain.
Nedergaard and her team were responsible for first uncovering the glymphatic system in a 2012 paper, revealing how large volumes of cerebral spinal fluid (CSF) are pumped through the brain each day to forcefully carry away waste.
In this new study, the team found that in mice consuming low levels of ethanol, roughly equivalent to 2.5 drinks per day in humans, CSF moved through the brain and removed waste more efficiently when compared to the teetotaling mice control group. The control and low dose groups also performed the same in cognitive and motor tests.
"The data on the effects of alcohol on the glymphatic system seemingly matches the J-shaped model relating to the dose effects of alcohol on general health and mortality, whereby low doses of alcohol are beneficial, while excessive consumption is detrimental to overall health," says Nedergaard. "Studies have shown that low-to-moderate alcohol intake is associated with a lesser risk of dementia, while heavy drinking for many years confers an increased risk of cognitive decline. This study may help explain why this occurs. Specifically, low doses of alcohol appear to improve overall brain health."
The team's study appears in Scientific Reports.