Drinking This Popular Beverage Can Shrink Your Brain, New Study Says
Researchers found that even a small daily amount can have immediate health consequences.
Whether you're reaching for a glass of tap water to kick your thirst or draining the coffee pot for a much-needed morning pick-me-up, the beverages we choose to sip on can clearly have an immediate effect on our bodies. But studies have shown that while some drinks can provide some surprising health benefits down the line, others can be considered as dangerous as an unhealthy diet by increasing your risk of heart disease, dementia, or cancer. Now, the latest research finds that one beverage in particular can actually shrink your brain—even when consumed in small amounts. Read on to see if what's in your cup could be putting your health at risk.
Having just one drink of alcohol daily can shrink your brain.
The latest research comes from a study published on Mar. 4 in the journal Nature, which analyzed data from 36,678 healthy adults across the U.K. who were middle-aged or older. The information included the self-reported number of "units" of alcohol consumed per week or month—with one standard drink in the U.S. being equivalent to 1.75 units in the U.K.—which were converted into units per day for purposes of the study. The team also had access to MRI brain scans for each participant that helped them measure the size of white and gray matter for all involved in the study.
Even after considering sex, age, BMI, genetic predispositions, and socioeconomic status, the researchers found a negative correlation between the amount of alcohol consumed and brain size. Participants aged 50 who drank four units of alcohol per day had a decreased brain matter equivalent to ten years worth of aging compared to those who didn't drink. But even those who only had two drinks of alcohol per day still saw the equivalent of two extra years' worth of aging compared to those who had one, shrinking both gray and white brain matter.
"Most of these negative associations are apparent in individuals consuming an average of only one to two daily alcohol units," the study authors wrote in their findings. "Thus, this multimodal imaging study highlights the potential for even moderate drinking to be associated with changes in brain volume in middle-aged and older adults."
The researchers concluded that those "already drinking the most" alcohol could see brain benefits from drinking less.
Ultimately, the researchers concluded that there was a clear correlation between increased alcohol consumption and decreased brain size. "It's not linear. It gets worse the more you drink," Remi Daviet, PhD, the study's first author and an assistant professor of marketing in the Wisconsin School of Business at the University of Wisconsin-Madison, said in a statement.
The team also credited the size of their data set for being able to return such findings. "The fact that we have such a large sample size allows us to find subtle patterns, even between drinking the equivalent of half a beer and one beer a day," Gideon Nave, PhD, one of the study's co-authors and an assistant professor of marketing at the Wharton School of the University of Pennsylvania, said in a statement. "Having this dataset is like having a microscope or a telescope with a more powerful lens. You get a better resolution and start seeing patterns and associations you couldn't before."
Still, Nave pointed out that the findings weren't necessarily bad news for those who find themselves overindulging. "The people who can benefit the most from drinking less are the people who are already drinking the most," he said.
Other experts said more research would be necessary to verify the findings.
However, despite the considerably large sample set used in the researchers' analysis, some experts pointed out that more information would be needed before a direct cause and effect could be established between brain size and alcohol consumption. "A problem in this study is that they only have information on people's drinking habits for the one year prior to the [brain] imaging," Emmanuela Gakidou, PhD, an alcohol researcher and professor of health metrics sciences at the University of Washington, told CNN. "I think this is a major limitation of the study as it's likely that the cumulative consumption of alcohol throughout one's lifetime is associated with the brain, not just the level of consumption right before the images were taken," she added.
However, she was optimistic that the findings could help push subsequent studies in the right direction. "The relationship between alcohol and health is complex, and our understanding of that relationship is evolving over time," Gakidou said. "Based on this study, I would not really draw any definitive conclusions, but I would say that the authors have identified areas for further research."
Other studies have found that even moderate amounts of alcohol can also harm heart health.
The controversial debate within the medical community on the potential health risks and benefits of moderate alcohol consumption isn't limited to just brain health, of course. According to a policy brief released by the World Heart Federation (WHF) on Jan. 20, the international medical organization warns that not only does a daily glass of wine not promote health benefits but that "no amount of alcohol is good for the heart."
"At the World Heart Federation, we decided that it was imperative that we speak up about alcohol and the damages to health, as well as the social and economic harms, because there is an impression in the population in general, and even among health care professionals, that it is good for the heart," Beatriz Champagne, PhD, chair of the advocacy committee that produced the report, told CNN in an email. "It is not, and the evidence has increasingly shown that there is no level of alcohol consumption that is safe for health."
According to the full policy brief released by the WHF, there were more than 2.4 million alcohol-related deaths in 2019, accounting for 4.3 percent of all mortality globally. "The evidence is clear: any level of alcohol consumption can lead to loss of healthy life," the WHF wrote in a press release announcing the brief. "Studies have shown that even small amounts of alcohol can increase a person's risk of cardiovascular disease, including coronary disease, stroke, heart failure, hypertensive heart disease, cardiomyopathy, atrial fibrillation, and aneurysm."