Excessive alcohol is known to be detrimental to health but new research claims having it in small doses can be good for the brain.
Tests on mice have shown low levels of alcohol consumption help the brain clear away toxins – including those associated with Alzheimer’s disease.
Study leader Maiken Nedergaard, of the University of Rochester Medical Center in New York, said: “Prolonged intake of excessive amounts of ethanol is known to have adverse effects on the central nervous system.
“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.”
According to the researchers, their findings add to “a growing body of research that point to the health benefits of low doses of alcohol”.
The rodents were fed small doses of alcohol – equivalent to a human consuming two-and-a-half drinks per day.
The researchers found the glymphatic system – which is the brain and the nervous system’s waste clearance pathway – was more efficient in removing waste, compared to control mice who were not exposed to alcohol.
The process works by pumping cerebral spinal fluid (CSF) into brain tissue, flushing away waste.
According to the researchers, this mechanism also helps keep at bay the proteins beta amyloid and tau that are associated with Alzheimer’s disease and other forms of dementia.
Ms Nedergaard said: “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.
“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.
“Specifically, low doses of alcohol appear to improve overall brain health.”
The study is published in the journal Scientific Reports.