Even moderate alcohol consumption may have adverse effects on brain health, finds study

Scientists call for revision of existing “low-risk” drinking guidelines

A waiter serves a cocktail at a bar on the eve of the mandatory closure of bars in Brussels (AFP via Getty Images)

Even moderate consumption of alcohol is associated with adverse affects on the brain, according to a new study of over 25,000 participants which calls for existing “low-risk” drinking guidelines to be revised.

While binge drinkers and individuals with high blood pressure and BMI may be more susceptible, the study, which is yet to be peer-reviewed, found “no safe dose of alcohol for the brain.”

Scientists, including Anya Topiwala from the University of Oxford, assessed the health profiles of 25,378 individuals from the UK Biobank – a database designed to help researchers understand the link diseases have with genetic and environmental factors.

They assessed each participant’s data, including their age, sex, BMI, blood pressure, self-reported alcohol consumption, and brain health from MRI scans.

The results revealed that a higher quantity of weekly alcohol consumption was associated with lower brain grey matter density even after accounting for individual differences in biological and behavioural traits among the participants.

“Alcohol consumption was linearly and negatively associated with indices of brain health across most of the brain. Additive harmful effects of alcohol volume and frequent binging were observed,” the scientists wrote in the study, posted in the preprint platform medRxiv.

Scientists believe the large sample size of the study enabled a deeper exploration of the association between alcohol consumption and brain structures such as the cortex and the cerebellum which was previously uncharacterised.

According to the researchers, higher volume of alcohol consumption per week as well as binge drinking could have additive effects throughout the brain irrespective of the type of beverage consumed.

While previous studies had found some benefits to wine drinking, the researchers say this could be due to associations of wine-drinking to higher socioeconomic status and educational attainment.

“If you look at who is moderately drinking, at least in this country, they are better educated, wealthier people that would do much better on a memory test … just because of who they are, than people that are less educated,” Ms Topiwala reportedly said.

Citing the limitations of the study, the scientists said the invitations for participants yielded only a 5 per cent response rate from the UKBiobank, adding that the sample was less ethnically diverse, healthier and better educated.

The researchers also added that the study was observational, and did not find any causal relationship between alcohol drinking and brain health.

While an official guideline issued by UK’s Department of Health in 2016 urges people to not consume more than 14 units of alcohol a week – which is close to five pints of beer at 5 per cent ABV strength – the scientists behind the current study say this measure needs to be revised, incorporating the recent findings.