With the holidays upon us, there's just one thought on many of our minds: How much can I drink?

That's only partly a joke. I personally don't drink much, but I do go to more parties at this time of year than any other. And we've all long been told that moderate drinking, actually, may have health benefits. So a glass of wine at dinner is not something I ever think twice about.

Maybe I should. New studies using brain imaging, highlighted in The Wall Street Journal, suggest that rather unimpressive levels of drinking can lead to noticeable damage to the brain. Researchers are even coining new terms for the results of long-term, not-all-that-much drinking, such as "alcohol-induced neurocognitive disorder" and "alcohol-related dementia." The Journal story refers to the potential causes of these disorders as "long-term alcohol abuse."

But how much alcohol, exactly, are we talking about here?

If you consider yourself a moderate drinker, you're not going to like the answer: 14 drinks a week for men and just seven for women. That's right: For women, a glass of wine with dinner every night is potentially enough to do long-term damage to your brain. The kicker: "Some people, though, experience severe effects at lower levels," according to the story.

One drink a day is the same amount of alcohol thought to help your cardiovascular health and mitigate the risk of depression, and often referred to as "moderate" drinking.

The researchers quoted don't discriminate between, say, a glass of red wine and a shot of tequila. Red wine has been particularly touted for its health benefits, thanks to the presence of antioxidants and a substance called resveratrol, thought to be good for the heart. "Drink Red Wine and Live Longer" was the headline of a Fortune cover story, back in 2007, profiling now-shuttered biotech company Sirtris, which was trying to isolate resveratrol and its reputed antiaging properties.

Unfortunately, repeated exposure to alcohol seems to shrink gray-matter cells and damage white-matter cells. The gray matter is responsible for areas such as learning, memory, and social function. The white matter connects the different parts of the brain. Edith Sullivan, a professor of psychiatry and behavioral science at Stanford University, likens the effect to "accelerated aging."

Live longer, with a compromised brain? Doesn't sound like a tradeoff most of us are willing to make.