Is Any Drink Safe for Your Brain?

 

Most of us have heard that a glass of red wine with dinner might be good for you, maybe even for your brain. A big study from 2025 says that may not be true. This semester, Dr. Jessica Hoffman from Loyola's Stritch School of Medicine talked to our class about how alcohol affects the brain, and her research helps explain why.

In September 2025, researchers from Oxford, Yale, and Cambridge published a study on alcohol and dementia in BMJ Evidence-Based Medicine (a shorter news summary). They looked at more than 559,000 adults, plus genetic data from about 2.4 million people. At first, the results looked familiar: light drinkers seemed to have a lower risk of dementia than both heavy drinkers and non-drinkers.

Then the researchers used genetics to take a second look. Some people are born with genes that make them more likely to drink, and since your health later in life can't change those genes, they're a fairer way to test cause and effect. With this method, the benefit of light drinking disappeared: the more people were likely to drink, the higher their dementia risk. The researchers also found that many people cut back on drinking before being diagnosed, so some "non-drinkers" may have quit because they were already getting sick.

Dr. Hoffman studies why alcohol feels rewarding and how to block that reward without affecting the rest of the brain. Her work focuses on AMPA receptors, which pick up glutamate, the brain's main "go" signal, and help the brain strengthen connections when we learn. Blocking these receptors everywhere causes problems with movement and thinking, so she focuses on a protein called TARP γ-8, which attaches to only some AMPA receptors in areas tied to reward and memory.

In a 2021 study, her team gave mice a drug that only blocks AMPA receptors attached to TARP γ-8. Male mice worked less for alcohol but just as hard for sugar water, so the drug seemed to target alcohol's reward specifically. It didn't work in female mice, which shows why treatments need to be tested in both sexes. A 2023 study found that the drug cut alcohol intake when put into the amygdala, but cut sugar intake instead when put into the hippocampus.

First, how it happens. The BMJ study shows that alcohol likely raises dementia risk, but not why. Alcohol acts on glutamate and AMPA receptors, the same tools the brain uses to make and keep memories. If each drink changes these systems a little, it makes sense that the risk would build with every drink, just like the genetic results showed. Dr. Hoffman's current research now looks at how alcohol use connects to Alzheimer's disease and brain injury.

Second, prevention. The BMJ researchers estimated that cutting alcohol use disorder in half could prevent up to 16% of dementia cases. But many people stop taking their medication because of side effects. A drug that lowers alcohol's pull without affecting movement or thinking, which is what the TARP γ-8 approach is going for, could help protect the aging brain, not just treat addiction.

Both studies have limits. The genetic method relies on assumptions that are hard to prove, and Dr. Hoffman's work was done in mice. Still, if light drinking isn't good for the brain, the way we talk about it may need to change, especially for people with extra risk, like those who have had a head injury.

If more research shows there's no safe amount of alcohol for the brain, should we start talking about drinking the way we now talk about smoking? 

Sources

• Topiwala, A., et al. (2025). Alcohol use and risk of dementia in diverse populations: evidence from cohort, case–control and Mendelian randomization approaches. BMJ Evidence-Based Medicine. doi:10.1136/bmjebm-2025-113913
• HealthDay News. (2025, September 24). Any amount of drinking increases dementia risk, study says.
• Hoffman, J. L., Faccidomo, S., Saunders, B. L., Taylor, S. M., Kim, M., & Hodge, C. W. (2021). Inhibition of AMPA receptors (AMPARs) containing transmembrane AMPAR regulatory protein γ-8 with JNJ-55511118 shows preclinical efficacy in reducing chronic repetitive alcohol self-administration. Alcoholism: Clinical and Experimental Research.
• Hoffman, J. L., Faccidomo, S. P., Taylor, S. M., DeMiceli, K. G., May, A. M., Smith, E. N., Whindleton, C. M., & Hodge, C. W. (2023). Negative modulation of AMPA receptors bound to transmembrane AMPA receptor regulatory protein γ-8 blunts the positive reinforcing properties of alcohol and sucrose in a brain region-dependent manner in male mice. Psychopharmacology, 240(6), 1261–1273.