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Does Drinking Alcohol Kill Brain Cells?

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Watch someone after they’ve had a few drinks, and you’ll find clear 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.”

But is this true? No. But alcohol does damage some of your 86 billion brain cells, or neurons, which send electrical and chemical messages within the brain and between it and other parts of the body. 

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. Fortunately, when you drink alcoholic beverages, your body tries not to let all of that ethanol roam around unchecked. Enzymes in your liver convert it first info acetaldehyde (which is highly toxic) and then into acetate, which is broken down into water and carbon dioxide and eliminated by your body.

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. What it does is inhibit the communication between dendrites, or branching connections at the ends of neurons that send and receive information between neurons, in the cerebellum, a part of the brain involved in motor coordination. This poor communication results in some of the typical impairments of intoxication. 

Researchers at Washington University in St. Louis found that alcohol, even when applied directly to neurons, didn’t kill them. 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 brain disorder 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 B1 (or thiamine) deficiency 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. 

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Why Adding Water to Your Whiskey Makes It Taste Better
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Don’t ever let people tease you for watering down your whiskey. If they’re true aficionados, they’ll know that adding a splash of water or a few cubes of ice to your drink will actually enhance its natural flavors. But how can something as flavorless as water make a barrel-aged scotch or bourbon taste even better? Chemists think they’ve found the answer.

As The Verge reports, researchers from the Linnæus University Centre for Biomaterials Chemistry in Sweden analyzed the molecular composition of whiskey in the presence of water. We already know that the molecule guaiacol is largely responsible for whiskey’s smoky taste and aroma. Guaiacol bonds to alcohol molecules, which means that in straight whiskey that guaiacol flavor will be fairly evenly distributed throughout the cask. Alcohol is repelled by water, and guaiacol partially so. That means when a splash of water is added to the beverage the alcohol gets pushed to the surface, dragging the guaiacol along with it. Concentrated at the top of the glass, the whiskey’s distinctive taste and scent is in the perfect position to be noticed by the drinker.

According to the team’s experiments, which they laid out in the journal Scientific Reports [PDF], whiskey that’s been diluted down to 40 percent to 45 percent alcohol content will start to show more guaiacol sloshing near the surface. Most commercial whiskey is already diluted before it's bottled, so the drink you order in a bar should fall within this range to begin with. Adding additional water or ice will boost the flavor-enhancing effect even further.

As for just how much water to add, the paper doesn’t specify. Whiskey lovers will just have to conduct some experiments of their own to see which ratios suit their palate.

[h/t NPR]

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Big Questions
If Beer and Bread Use Almost the Exact Same Ingredients, Why Isn't Bread Alcoholic?
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If beer and bread use almost the exact same ingredients (minus hops) why isn't bread alcoholic?

Josh Velson:

All yeast breads contain some amount of alcohol. Have you ever smelled a rising loaf of bread or, better yet, smelled the air underneath dough that has been covered while rising? It smells really boozy. And that sweet smell that fresh-baked bread has under the yeast and nutty Maillard reaction notes? Alcohol.

However, during the baking process, most of the alcohol in the dough evaporates into the atmosphere. This is basically the same thing that happens to much of the water in the dough as well. And it’s long been known that bread contains residual alcohol—up to 1.9 percent of it. In the 1920s, the American Chemical Society even had a set of experimenters report on it.

Anecdotally, I’ve also accidentally made really boozy bread by letting a white bread dough rise for too long. The end result was that not enough of the alcohol boiled off, and the darned thing tasted like alcohol. You can also taste alcohol in the doughy bits of underbaked white bread, which I categorically do not recommend you try making.

Putting on my industrial biochemistry hat here, many [people] claim that alcohol is only the product of a “starvation process” on yeast once they run out of oxygen. That’s wrong.

The most common brewers and bread yeasts, of the Saccharomyces genus (and some of the Brettanomyces genus, also used to produce beer), will produce alcohol in both a beer wort
and in bread dough immediately, regardless of aeration. This is actually a surprising result, as it runs counter to what is most efficient for the cell (and, incidentally, the simplistic version of yeast biology that is often taught to home brewers). The expectation would be that the cell would perform aerobic respiration (full conversion of sugar and oxygen to carbon dioxide and water) until oxygen runs out, and only then revert to alcoholic fermentation, which runs without oxygen but produces less energy.

Instead, if a Saccharomyces yeast finds itself in a high-sugar environment, regardless of the presence of air it will start producing ethanol, shunting sugar into the anaerobic respiration pathway while still running the aerobic process in parallel. This phenomenon is known as the Crabtree effect, and is speculated to be an adaptation to suppress competing organisms
in the high-sugar environment because ethanol has antiseptic properties that yeasts are tolerant to but competitors are not. It’s a quirk of Saccharomyces biology that you basically only learn about if you spent a long time doing way too much yeast cell culture … like me.

This post originally appeared on Quora. Click here to view.

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