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Alcohol: The Good and the Bad

What do we make of alcohol? In sufficient amounts, it’s a poison. It’s incredibly addictive. It destroys entire communities [7]. It tears families apart and compels otherwise reasonable, upstanding individuals to commit terribly senseless acts. On the other hand, it’s a powerful social lubricant. The good stuff tastes great and can enhance the healthfulness of certain foods while inhibiting the unhealthfulness of others. It’s fun, it’s pleasurable, and it brings real (if chemically enhanced) joy to people. Moreover, we have a long and storied history with alcohol; it’s been an integral part of human culture and society for thousands, if not tens of thousands, of years.

So, what’s the deal? Is it good, or is it bad? Is it poison, or is it a gift? Let’s take a look at both sides of the story, which, as is often the case, isn’t exactly black and white:

First, the downsides.

It’s toxic.

Our ability to break alcohol down into less toxic metabolites didn’t arise because of our tendency to seek out fermented [8] fruits. Over the course of an average day, the average human digestive system produces about three grams of ethanol just from the gut flora [9] fermenting the gut’s contents. If we didn’t have the ability to metabolize and detoxify ethanol, those three grams would add up real quick and represent a huge toxin load on our bodies. After alcohol is consumed, a number of enzymatic reactions ensue. In the liver, an enzyme called alcohol dehydrogenase converts the ethanol to acetaldehyde, an incredibly toxic compound that’s been implicated in causing many hangover symptoms. An enzyme called acetaldehyde dehydrogenase converts the acetaldehyde into acetic acid, or vinegar [10] (which is harmless unless you’re a cucumber). From there, you’re good to go. Sounds simple enough, right? Just let the enzymes do their thing. As long as you make those enzymes, the alcohol will be safely and effectively metabolized into table vinegar which can then be extracted to form a delicious salad dressing (that last part isn’t true).

Unfortunately, not everyone produces the same amount and quality of detoxifying enzymes. Many people of East Asian descent possess a dominant mutation in the gene that codes for aldehyde dehydrogenase, making it less effective. While they’re less likely to be alcoholics, folks with the mutation (characterized by a “flushing” upon ingestion) are at an elevated risk of liver damage and esophageal cancer [11].

It can give you fatty liver (and worse).

Around these parts, we usually talk about non-alcoholic fatty liver, a disease associated with sugar [12] and fat intake coupled with inadequate choline to support the liver’s function. But notice that we have to qualify it with “non-alcoholic.” That’s because the most-studied type of fatty liver is alcoholic fatty liver. The mechanisms behind alcoholic fatty liver are myriad and multifaceted [13], but it ultimately comes down to the fact that you’re bathing your liver in a known toxin. Liver alcohol metabolism increases the NADH/NAD+ ratio, thereby promoting the creation of liver fat cells and a reduction in fatty acid oxidation; the result is added fat in the liver and impaired fat burning [14]. Acetaldehyde, especially if it lingers for too long, also induces inflammation in the liver, which can ultimately progress to full cirrhosis and liver failure.

It can be carcinogenic.

Excessive alcohol intake is an established epidemiological risk factor for several cancers [15], including stomach, liver, and colon cancer (to name just a few; more than a dozen cancers are linked to alcohol abuse). In the stomach and liver, alcohol dehydrogenase converts ethanol into acetaldehyde, which is inflammatory and toxic. Alcohol that makes it through the stomach into the small intestine is also oxidized into acetaldehyde, this time by gut flora. While the liver produces the necessary enzymes to break down acetaldehyde into acetic acid, our gut microbes aren’t so well equipped and the acetaldehyde is allowed to linger longer.

It’s addictive.

While I’d argue that being addicted to anything will have a negative effect on your life, if not your physical health, being addicted to alcohol is particularly harmful because of how toxic it is – especially the more you drink. To get an idea of just how addictive it is, check out the results of this study [16]: alcohol is less addictive than nicotine, crystal meth, and crack, but more addictive than heroin, intranasal amphetamine, cocaine, and caffeine. One’s susceptibility to alcohol addiction is often hereditary [17], too, meaning some people will be far more likely to become addicted than others.

It disrupts sleep.

A nightcap is a misnomer. Sure, it’ll help you fall asleep, but your sleep won’t be any better. In fact, as plenty of people reminded me in the comment section of last week’s post on sleep, alcohol is a serious disrupter of sleep quality [18]. It increases the incidence of sleep disruptions, and it perturbs the healthy sleep cycles.

It affects judgment and perception.

Even though alcohol destroys a person’s ability to safely maneuver a motor vehicle, one in three car accidents that result in death involve drunk drivers [19]. Everyone knows that you shouldn’t drive drunk, but why does it keep happening? A recent study even showed that just a single drink caused subjects to find “intentionality” in other people’s actions (PDF [20]). Subjects who got the alcohol were less likely to view simple actions as accidental, rather than intentional. Thus, when you’re under the influence of alcohol, you’re more likely to take personal offense at the guy bumping into your shoulder, the lady stepping on your shoe, or the person “staring” at you from across the bar. Because, after all, they “meant” to do it, right? The title of the study sums it up quite nicely: “‘There’s No Such Thing as an Accident,’ Especially When People are Drunk.”

It promotes bad eating.

Everyone who’s ever gotten at least a buzz from a glass or two of wine or a mixed drink has felt the often irresistible urge to snack, to order something salty, crunchy, and sweet from the menu, to beg the driver to swing by the greasiest nastiest fast food drive-thru. This is a well-documented phenomenon. Alcohol affects both active overeating and passive overeating. Active overeating describes the conscious decision to “get some grub.” Passive overeating describes the amount you eat once the food is in front of you. Both are enhanced by alcohol [21]. This wouldn’t be such a bad thing if you’re drinking at a Primal meet-up, where you’re surrounded by relatively healthy food, but that’s not where most drinking occurs.

It gives hangovers.

What’s worse than a bad hangover? I’m unaware of anything, at least on a physical scale. Sure, you can mitigate the damage [22], but the fact that a hangover even exists tells us that whatever we’re ingesting that gave us the hangover is bad for us (in the amount we ingested, at least).

But what about the positives?

It improves endothelial function (with a catch).

Impaired release of nitric oxide from the endothelial [23] cells is strongly associated with cardiovascular disease [24]. Ethanol actually increases the production of nitric oxide [25], which dilates blood vessels, regulates blood pressure, induces vascular smooth muscle relaxation, and basically improves endothelial function. If you want good cardiovascular health, you want good endothelial function. However, it’s important to note that large doses of ethanol seem to decrease endothelial function [26], so caution is obviously warranted.

It can reduce stress.

A lot of people use a glass of wine or beer to “wind down” after a hard day. This sounds bad on the surface – “you’re relying on alcohol to stay sane!” – but really, if you have to choose between stewing in your stress hormones [27] all day and night and having a drink or two to settle yourself down, I think the drink can be a better option for some people – particularly if the stress is going to impair your sleep and affect your relationships. You’ll want to identify and deal with the original source of the stress, of course, but some people may find a net benefit from having that drink.

It promotes socializing.

Humans are social animals, and we are happiest and healthiest when we have friends, loved ones, and spend quality time with them. Social isolation is a consistent and strong risk factor for increased mortality and morbidity [28] (meaning it’s linked with earlier death and worse health in the days up until that death). You shouldn’t base your socialization entirely on drinking alcohol, but it can certainly be a powerful enhancer of your social life, and if you’re having a couple of glasses of wine as you host dinner parties, hang out with friends, enjoy a candlelit dinner with your significant other, or throw a BBQ with your social circle, it will likely have a net positive effect on your health. Of course, this isn’t to say that alcohol is any way needed to have a good time in a social setting.

It can reduce post-prandial blood sugar and lipid peroxidation (when taken with a meal).

Just like it says above, drinking alcohol (like wine, for example) with food can reduce postprandial blood glucose [29] and the susceptibility of blood lipids to peroxidation (PDF [30]).

It can lower iron absorption if you’ve got iron overload.

Although the conventional push is to increase the intake of iron from foods (especially via fortified grains [31]), some people don’t actually need the added iron. If you have hemochromatosis, a genetic condition that probably arose in Europeans as a survival response to the bubonic plague, you are a hyper-absorber of dietary iron. Luckily, ethanol seems to inhibit the absorption of heme iron [32], the kind you find in red meat. Red wine is also effective at reducing non-heme iron absorption [33], an effect most likely due to the polyphenols present. That said, the entirely non-alcoholic black tea also inhibits iron absorption and has even been shown to reduce the frequency of blood-draws required in patients with iron overload [34]. Coffee works [35], too.

If you’re going to drink:

Have it with food.

When you eat a meal, and your stomach is “full,” the pyloric sphincter – which controls the passage of food and drink from the stomach into the small intestine – closes up until your stomach can break down its contents. Any alcohol added to a full stomach will also spend more time being broken down by the relevant enzymes. If you drink on an empty stomach, the pyloric sphincter is wide open, and a greater proportion of alcohol will make it to the small intestine for immediate absorption. Plus, as I mentioned earlier, drinking alcohol with food can reduce postprandial blood glucose [29] and the susceptibility of blood lipids to peroxidation (PDF [30]). Keeping your drinking around meals will let you take advantage of these benefits.

Focus on alcoholic drinks with greater fluid content.

Shots of plastic bottle vodka (or even the best vodka) are concentrated sources of ethanol, and as long as we’ve been nibbling on fermented fruits and brewing up Paleolithic moonshine from mushrooms and honey, consuming concentrated, distilled ethanol in the form of rum, gin, whiskey, vodka, and other hard liquors [36] is a relatively recent practice. Some accounts [37] suggest that the Chinese were distilling rice liquor in 800 BC, while others say it wasn’t until the 12th century AD that distillation became commonplace across the “known” world. At any rate, one could certainly argue that alcohol with a low fluid content is an evolutionarily novel food item. Less fluid means less “stuff” in your stomach, which means a more open and allowing pyloric sphincter, which means faster absorption through the small intestine. More fluid means more “stuff” in your stomach and a more restrictive pyloric sphincter and slower absorption. You could even make like the ancient Greeks and water down your wine, which some people seem to think actually improves the wine [38].

Choose your drinking companions wisely.

Even among voles, peer pressure-induced binge drinking is a reality. If that super cool vole with the sweet facial hair is double fisting acorn shells filled with dandelion wine, you’ll be subconsciously drawn to do the same [39]. If your group of friends gets absolutely obliterated every time you go out with them, you’re more likely to join in on the “fun.” [40]

Drink moderate amounts.

All the research suggesting health benefits to drinking [41] revolves around “moderate drinking,” which is one, two, or three drinks a day. They’re not talking about pounding shots, or drinking Long Island iced teas, or doing Jello shots (although the gelatin might help matters). They’re talking about a glass or two of something.

Have everything else in line.

If you want to drink and remain healthy, you should strive to eat healthy [42], exercise well [43], reduce stress [44], walk a lot [45], experience nature [46], hang out with friends and loved ones [47], get sun when available [48], avoid nighttime light exposure [49] as much as possible, and every other lifestyle prescription I recommend. In short, alcohol can augment (or at least fail to impact either way) an already healthy lifestyle, but it probably won’t make a bad situation better.

Full disclosure: I drink. My drink of choice is red wine [50], and I might do a glass or two most nights, but I never get drunk. Heck, I don’t even really get “buzzed.” I’d never recommend that people take up drinking or continue drinking, but I also don’t see it as a great evil in and of itself. The dose and frequency make the poison; it’s just that depending on a number of factors, the dose that makes alcohol a poison might be lower or higher for you than for me. If your sleep is affected or you are the least bit “off” the next day, you probably surpassed your ability to effectively process it and you should factor that in to your choice and approach to drinking again. And remember, alcoholism is a serious issue for some people and I am in no way suggesting there is any “workaround” or excuse herein for someone with those issues, or that drinking, even in moderation, is necessary or optimal for healthy living.

Okay, that’s about it for me. Let’s open it up to you guys, now. I want to hear your thoughts on alcohol, especially whether it’s had a positive, negative, or neutral effect on your life and the life of those you care about. I want to hear how you’ve integrated alcohol into your otherwise healthy lifestyle (or not). Thanks for reading!