Last year, a study carried out by researchers at the University of Oxford concluded that drinking any amount of alcohol is harmful to the brain ; in fact, they linked moderate alcohol consumption with a lower volume of gray matter (that area of the brain that has a high content of neural cell bodies and plays an important role in the central nervous system).
The more alcohol, the less gray matter
The study included 25,378 participants from the UK Biobank, a long-term study investigating the development of health problems. The researchers looked at each person’s alcohol consumption, determined using questionnaires, as well as brain MRIs and other personal data, such as age, education and lifestyle, such as smoking. A higher volume of alcohol consumption per week was associated with lower gray matter density, reaching up to a 0.8% reduction in gray matter volume.
The scientific literature on the effects of drinking alcohol in moderation has always given mixed results. For one thing, some studies have found that a glass of red wine a day can stave off diseases like type 2 diabetes, osteoporosis, Alzheimer’s, and heart disease. But the results of this study were clear: “there is no safe dose of alcohol for the brain” and say that moderate consumption is associated with “more widespread adverse effects on the brain than previously recognized.”
Virtually the entire brain appears to be affected by alcohol consumption and not just specific areas , as previously thought, the authors said. There is no healthy relationship between excessive alcohol consumption and the brain.
Any amount of alcohol is harmful to the brain
Now, a new study has found an even stronger link between alcohol consumption, even at levels most would consider moderate (a few beers or glasses of wine a week), and its risks to the brain.
Researchers led by experts from the University of Pennsylvania analyzed data from more than 36,000 adults, finding that light to moderate alcohol consumption was associated with reductions in overall brain volume. They employed biomedical data, specifically looking at brain MRIs that can be used to calculate white and gray matter volume in different brain regions.
The more alcohol, the smaller the brain
The link became stronger the higher the level of alcohol consumption; Thus, in 50-year-olds, as the average person’s alcohol consumption increased from one unit of alcohol (about half a beer) a day to two units (a pint of beer or a glass of wine), they produced associated changes in the brain like the equivalent of aging two years. Drinking two to three units of alcohol at the same age was like aging three and a half years.
“The fact that we have such a large sample allows us to find subtle patterns, even between drinking the equivalent of half a beer and one beer a day,” explains Gideon Nave, leader of the study published in the journal Nature Communications.
The results held up controlling for confounding variables such as age, height, gender, smoking, socioeconomic status, genetic ancestry, or place of residence. They also corrected brain volume data for total head size.
Going from zero to one unit of alcohol didn’t make a big difference in brain volume, but going from one to two or two or three units a day was associated with reductions in both gray and white matter.
“It is not linear. It gets worse the more you drink,” say the authors.
“There is some evidence that the effect of drinking on the brain is exponential. So one additional drink in one day might have more impact than any of the previous drinks that day. This means that reducing the last drink of the night could have a great effect in terms of brain aging”, concludes Remi Daviet, co-author of the work.
The researchers hope these findings will prompt regular drinkers to reconsider how much they drink.
Referencia: “Associations between alcohol consumption and gray and white matter volumes in the UK Biobank” 4 March 2022, Nature Communications.
DOI: 10.1038/s41467-022-28735-5
Referencia: No safe level of alcohol consumption for brain health: observational cohort study of 25,378 UK Biobank participants 2021 Anya Topiwala, Klaus P. Ebmeier, Thomas Maullin-Sapey, Thomas E. Nichols doi: https://doi.org/10.1101/2021.05.10.21256931
