Homer Simpson famously called alcohol “the cause of, and solution to, all of life’s problems.” While America’s favorite jaundiced patriarch probably wasn’t talking about dementia, alcohol actually has been extensively studied as a causal and preventative factor. So, is drinking alcohol good or bad for the brain? Overall, the research is mixed. 

Some studies find that people who drink a bit of alcohol or red wine have a lower risk of developing dementia than nondrinkers. Other studies found no protective effects, instead linking frequent drinking to a higher dementia risk. Other studies have characterized how excessive drinking and addiction could lead to the development of a condition called Wernicke-Korsakoff syndrome, which causes memory loss and cognitive impairment, not unlike Alzheimer’s disease.

Does that mean Homer Simpson was right? Well, it’s complicated.  

Drinking: does it protect or predispose the brain to dementia? 

It isn’t very easy to study the links between drinking and dementia—most studies involve looking back on people’s health records and using surveys to try and figure out how often they’ve been drinking. Researchers who looked at all these studies back in 2012 concluded that it’s really hard to make heads or tails out of it. 

But over the last decade, some research has come out that provides slightly more definitive answers. 

While some studies suggest that drinking small amounts of alcohol is linked to a reduction in dementia compared to nondrinkers, this effect may be explained by other factors. For people who manage to abstain from alcohol after years of heavy drinking, the damage to the brain might be permanent. Other people who don’t drink as often might also be more likely to have other underlying risk factors for dementia, like heart disease. 

One thing that researchers are now more confident about is that frequent drinking and alcohol addiction are linked to higher dementia risk. A 2023 study found that around three percent of dementia cases in women and about eight percent of cases in men could be attributed to frequent drinking—in some of these cases, causing Wernicke-Korsakoff’s syndrome. 

A detour to wine country  

Is red wine a special case when it comes to dementia prevention?  

Red wine contains chemicals produced by the grapes called flavonoids, which have been shown, in animal models and Petri dishes, to boost brain function and memory. Unfortunately, this hasn’t translated well into human trials because you’d need to drink hundreds or thousands of bottles of wine to receive the same amount of flavonoids as administered in these studies. 

Some studies that looked at health records and surveyed people about their diet have found that people who drink moderate amounts of red wine might have a lower chance of developing dementia. However, these studies might be influenced by other factors like socioeconomic status, which have a very big impact on both diet and dementia risk.  

There’s an adage used in pharmacology: The dose makes the poison. At high enough levels, almost anything, including water, can be dangerous. When it comes to alcohol and dementia, it looks like the more you drink, the higher your risk—there isn’t any conclusive evidence that moderate drinking is protective, just that it might be less bad for you.