March 17, 2022—For many years, it's been well-known that drinking too much alcohol raises the risk of dementia and other health problems. But how much alcohol use is too much?
It may be less than you'd think, according to a new study published in the journal Nature. Researchers found people who drank as little as one to two units of alcohol a day—about half a pint of beer to a glass of wine—showed measurable decreases in brain size. And the effects increased the more people drank.
Researchers reviewed brain images of more than 36,000 healthy middle-aged and older adults from the UK Biobank, a nonprofit repository of health data. The study volunteers answered survey questions about their daily alcohol use.
The researchers found:
- Any level of alcohol use affects brain size. The volume of the brain's main tissues, called gray matter and white matter, was less in people who drank, compared to those who didn't. Also, women and men were similarly affected.
- Emotion, judgment and memory, among other brain functions, are at risk. The areas most affected by alcohol-induced shrinkage were the frontal, parietal and insular lobes. According to BrainLine, damage to these areas can affect emotions and impulse control, language, memory, body movement, and more. The connections leading from the hippocampus, which controls memory and learning, were also affected.
Beyond the brain
The new study demonstrates that, when it comes to brain health, even one or two drinks a day can harm your brain. But excessive alcohol use has long been linked with a variety of health problems. These include heart disease, cancer and liver disease.
If you'd like help to change your drinking habits, talk to your healthcare provider. This assessment can help you decide if it's time.