Does Drinking Kill Brain Cells?
Reader Scott wrote in to ask, “Does alcohol kill brain cells?”
“Oh, Lisa, you and your stories. ‘Bart is a vampire.’ ‘Beer kills brain cells.’ Now let’s go back to that…building…thingy, where our beds and TV…is.” - Homer Simpson
Watch someone after they’ve had a few drinks, and you’ll find evidence that alcohol does something to their brain. They stumble, slur their words, lose control of their emotions, and forget things.
Some people have tried to explain this behavior as the aftermath of cell death caused by alcohol. Often, it’s packaged as a neat factoid like “Three beers kill 10,000 brain cells.”
Now, ethyl alcohol (the kind found in boozy beverages, also known as ethanol) can kill cells and microorganisms. That’s what makes it an effective antiseptic. Your brain contains a few billion cells called neurons that send electrical and chemical messages between it and the other parts of the body. Obviously, you don’t want these little guys dying en masse.
Fortunately, when you drink alcoholic beverages, your body tries not to let all of that ethanol roam around unchecked. Rather, your liver processes it and converts it into less toxic stuff. The liver can only work so fast, though, processing about 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of distilled spirits per hour. If you’re knocking drinks back fast enough that your liver can’t keep up, the excess alcohol hangs out in the blood and travels through the body until it can be processed.
When this alcohol reaches the brain, it doesn’t kill the cells outright. What actually happens, according to Roberta Pentney, a cell biologist who studied alcohol and brain function for decades at SUNY Buffalo, is that the alcohol damages the parts of the cells that send and receive information. This causes problems with the way the cells communicate with each other and results in some of the impairments of intoxication.
Researchers at Washington University found that alcohol, even when applied directly to neurons, didn’t kill them. Like in Pentney’s work, it just interfered with the way they transmit information. Specifically, the researchers showed that alcohol causes certain receptors on neurons to manufacture steroids that inhibit memory formation.
Some alcoholics can experience neuron death as part of a disease called Wernicke-Korsakoff syndrome. In these cases, the evidence again suggests that the disease and cell death aren’t caused by the alcohol itself, but a deficiency in the B vitamin thiamine and general malnutrition that often go hand in hand with alcoholism.
For moderate drinkers, a number of studies from the last 15 years suggest that, far from killing brain cells, a little tipple is actually associated with a reduced risk of cognitive decline and dementia.