New Delhi: A new study has found that any amount of alcohol consumption is harmful to the brain.
The study conducted by researchers at the University of Oxford on 25,000 people using the UK Biobank said: “No safe dose of alcohol for the brain was found. Moderate consumption is associated with more widespread adverse effects on the brain than previously recognised.”
It added: “Individuals who binge drink or with high blood pressure and BMI may be more susceptible. Detrimental effects of drinking appear to be greater than other modifiable factors. Current ‘low risk’ drinking guidelines should be revisited to take account of brain effects.”
The authors highlighted that theirs is an observational study, and causality cannot be established from this association. But the study has been adjusted for other ‘confounders’ or factors that could inadvertently affect the results, like age, health, and comorbidities.
The study is yet to be peer-reviewed.
How it was conducted
The study was conducted using the UK Biobank, a substantial database designed to help researchers decode the genetic and environmental factors, including lifestyle and nutrition, that lead some people to develop diseases while others do not.
The study was conducted on 25,378 participants using data such as age, sex, education, self-reported alcohol consumption, brain size and health from MRI scans, information about hospital and outpatient visits, and memory tests. As many as 11,854 participants were women, and 60 per cent of the participants were above the age of 50.
Participants were judged on a variety of tasks and tests, including numerical and alphanumerical sequences, tower rearranging, digit substitution, pair matching, and pattern completion.
Participants’ brain activity and health were scanned using MRI machines. Data was adjusted for other factors like age, sex, smoking status, educational status, BMI, exercise, blood pressure, etc.
What the study found
While moderate alcohol consumption is common and often viewed as harmless to brain health, the study found any consumption reducing grey matter. “Moderate consumption is associated with more widespread adverse effects on the brain than previously recognised,” it concluded.
“Higher volume of alcohol consumption per week was associated with lower grey matter density almost globally,” the study said. It also found that alcohol consumption made a larger contribution than any other modifiable risk factor tested, including smoking.
Widespread negative associations were also seen between alcohol consumption and integrity of white matter, the brain fibers that scaffold the billions of neurons that make up grey matter.
“Those binging daily had a significantly lower total grey matter volume than never bingers,” the study said.
It also found that underlying conditions such as high blood pressure and BMI “steepened the negative association between alcohol and brain health”.
While the study is one of the largest imaging investigations into the impact of alcohol consumption on brain health to date, the researchers admitted to some limitations. They said that since the UK Biobank has been used, the sample is of healthier, better educated, less deprived with less ethnic diversity than the general population.
The study also said the proportion of participants who were drinking very heavily, or were alcohol dependent, was extremely low.
“There’s no threshold drinking for harm — any alcohol is worse. Pretty much the whole brain seems to be affected — not just specific areas, as previously thought,” said the lead author, Anya Topiwala, a senior clinical lecturer at the University of Oxford to The Guardian.
The study authors concluded that the “current ‘low risk’ drinking guidelines should be revisited to take account of brain effects”.