Alcohol, quite rightly, gets a bad press from doctors, scientists, and your liver. Recent years have brought increasingly more studies that show how alcohol, even in moderation, is an enemy of good health.
On the other hand, a new study has suggested that drinking one alcoholic drink a day could be linked to a reduced risk of developing dementia. But don't "cheers!" just yet, it might not be as straight-forward as it first sounds.
Research published in the British Medical Journal has followed over 9,000 British people for the past 23 years looking at the link between alcohol consumption and risk of dementia. This observational study – which didn’t look for a specific cause and effect – found middle-aged people had a 45 percent higher risk of developing dementia, compared to people who drank between one and 14 units of alcohol every week.
The underlying mechanism is not clear, so it would be foolish to think it’s as simple as knocking back a beer each night will keep your brain healthy, as there could be many different lifestyle factors at play.
Nevertheless, the study definitely raises some interesting questions.
“This study is yet another demonstration of the increased risks faced by alcohol abstainers compared to moderate drinkers,” noted Professor David Spiegelhalter, Winton Professor for the Public Understanding of Risk at the University of Cambridge, who was not involved in the study.
“Of course abstainers may be different in many ways other than not drinking alcohol, and it seems important to understand the reasons for these robust and important associations.”
Dr Sara Imarisio, head of research at Alzheimer’s Research UK, also pointed out: “People who completely abstain from alcohol may have a history of heavy drinking and this can make it difficult to interpret the links between drinking and health.”
While this study didn’t look for an underlying cause behind this correlation, separate studies have hinted at one. Earlier this year, researchers from the University of Rochester in New York carried out an experiment on mice – not humans – that found low levels of alcohol appear to spark up the glymphatic system, known as the brain’s waste disposal system. During our sleep, the glymphatic system “flushes” out toxins created by the brain. In turn, this can stop the build-up of beta-amyloid, a sticky protein found in the brains of people with Alzheimer’s disease.
That said, as the BMJ’s Editorial on the paper notes: “It’s complicated.”
“This study is important since it fills gaps in knowledge, but we should remain cautious and not change current recommendations on alcohol use based solely on epidemiological studies," it continues.
“In summary, alcohol consumption of 1-14 units per week may benefit brain health; however, alcohol choices must take into account all associated risks, including liver disease and cancer.”