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Millions of years ago, before humans walked the earth, a monkey discovered a novel treat on the rainforest floor: a piece of overripe fruit. The strong ethanol smell from the fermenting flesh drew him to the produce's precious calories, and the fruit was safe to eat because the alcohol repelled bacteria. He enjoyed the taste, and experienced a pleasant rush and a full stomach. Monkeys attracted to the scent and taste of alcohol may have had a selective advantage: they were able to find and eat more nutritious fruit than those not enticed by it, improving their health and enabling them to reproduce more often. It follows that these well-fed monkeys were also more likely to pass on genes predisposing their progeny to seek out this tasty, easily digestible discovery—and that, eventually, these genes found their way into humans.
This so-called "drunken monkey" hypothesis, espoused by Robert Dudley, Ph.D., an evolutionary physiologist at the University of California, Berkeley, while controversial, could explain the beginnings of our obsession with booze. Today, 73 percent of Americans regularly consume alcohol, up from 65 percent in 2002, according to recent research published in the journal JAMA Psychiatry. We socialize around cocktails, we toss back beers watching sporting events, we ease a stressful day with a nice glass of whatever you like. And not only are more of us drinking, but the study found we're also drinking more heavily. High-risk alcohol consumption among women has increased 58 percent since 2002, and alcohol use disorder has shot up 84 percent. In men, high-risk consumption has risen 16 percent, while alcohol use disorder has gone up 35 percent. (See "Drinking Defined," below for what's considered risky alcohol consumption.) Among older Americans 65 and over, those numbers are even higher: a 65 percent and 107 percent respective uptick.
Sobering stats, considering how bad excessive alcohol consumption is for our bodies. But maybe not as sobering as the recent news that even those of us who drink responsibly may be putting our health at risk. Last fall, a large, global review of studies published in The Lancet declared that "No amount of alcohol is safe to consume." Period. End of sentence. And a flood of flashy headlines from every major news outlet followed—amplifying the study's conclusion and summarily contradicting the decades-old belief that moderate alcohol consumption benefits heart health.
So does this mean we should give up our nightly glass?
No. Not at all.
When you dig into the subtleties and limitations of this shiny new study—and, very importantly, give weight to the fact that, for many, drinking is a basic innate pleasure, as that monkey discovered—the facts are far from the buzzkill they've been made out to be.
To be clear, no one disputes that regularly overimbibing is a serious health issue. Alcohol is a toxin, after all. In high amounts over many years, drinking can damage your liver, blood vessels and heart. It also increases inflammation and blood pressure and may alter gene expression, leading to various types of cancer and other problems. And at some point, heavy drinking can become a full-blown addiction. The controversy lies in whether moderate drinking—a nice glass of cabernet or IPA—is safe.
Alcohol Called into Question
For years, we have been told yes, sip away—it's good for your heart. (Although there is evidence linking alcohol use with cancer risk, particularly breast cancer.) That advice goes all the way back to the 1990s, when the low-fat craze held Americans in its sway—and we were terrified that eating fat in any form would give us heart disease. But then in 1991, 60 Minutes aired an episode on the French paradox—the realization that even though French people had high-fat diets that included buttery croissants, frites and Brie, their risk of cardiovascular disease was low. The host, Morley Safer, asked Serge Renaud, M.D., Ph.D., a research scientist at the prestigious French National Institute of Health and Medical Research, why. His answer: moderate amounts of red wine with meals. Americans rejoiced—drinking wine can save our hearts from our high-fat diets!—and wine sales skyrocketed. In 1992, Renaud followed the claim with a study backing up his theory. And research on resveratrol, an antioxidant in red wine believed to protect against heart disease and promote longevity, followed in the mid-'90s. (See "The Urban Legend of Resveratrol," below, for more on that.)
But since then, studies on larger groups of people, using more modern methods, have been quietly building the case that drinking alcohol actually doesn't offer these benefits. And 2018 was a particularly bad vintage for those imbibing under the guise of health. Max Griswold, M.A., a senior research scientist at the University of Washington, published the headline-grabbing Lancet study in collaboration with hundreds of colleagues from around the world. It wrapped together a massive amount of data from 195 countries into one magnum of a paper.
The researchers tried to fix a few problems found in previous studies: people's memories of food and beverage consumption are notoriously inaccurate, so in addition to surveying participants on their drinking habits, they also used data on alcohol sales and even adjusted for the amount tourists drank and for those brewing at home. Most previous research on the health outcomes of alcohol intake simply compared people who drank to those who didn't. But there's a big problem with that. Often, people who abstain have a health problem, a history of addiction or a family member with alcoholism—which is why they choose not to drink. In addition, many people who eschew alcohol do so because they can't afford it. (The JAMA Psychiatry study found that 64 percent of people with household incomes under $20,000 a year drink, compared to 81 percent of those earning $70,000 or more.) And lower incomes are associated with poorer health. So while in previous studies it seemed like alcohol was the reason moderate drinkers had a lower risk of heart disease and other problems, it may have actually been because teetotalers tend to be less healthy.
Griswold and his fellow study authors took all that into consideration as they analyzed 592 previously conducted studies for the effect of alcohol on 23 different health outcomes, including accidents, cancers, diabetes, several different heart conditions, liver disease and stroke, in addition to adding their new data and methods of processing the information. Their conclusion: "The level of alcohol consumption that minimized harm across health outcomes was zero standard drinks per week." Even though the researchers did see a lower risk for coronary heart disease—the type that can lead to heart attacks—among men and women having about one drink a day (a 14 and 18 percent drop, respectively), the odds of all sorts of cancers increased with each serving of alcohol. And just like that, word that no amount of alcohol was safe spread like red wine on a white tablecloth. "I got a lot of inquiries from patients," says David Katz, M.D., M.P.H., director of the Yale University Prevention Research Center at Griffin Hospital and EatingWell advisory board member. "No question, the study really resonated and made people anxious."
However, look at the data more closely—and even speak to Griswold himself—and it's clear that these findings are not so different from a number of other recent studies that came to very different conclusions. This April, for example, Angela Wood, Ph.D., a biostatistician at the University of Cambridge, published a paper (also in The Lancet) that examined alcohol's effects on different types of cardiovascular disease and death from any cause. After following almost 600,000 people for seven and a half years, on average, Wood found that the more you drink, the higher your odds of stroke, heart failure, fatal hypertensive disease, fatal aortic aneurysm and coronary disease. Heart attack risk, on the other hand, was 6 percent lower among those consuming 100 grams of alcohol a week, or about a drink a day. Plus, overall risk of death didn't increase much at all until a person had more than that one daily drink. According to Wood's study, drinking moderate amounts of alcohol is not dangerous to your health. And a June 2018 study in PLoS Medicine found that alcohol intake of between one and three drinks a week did not raise cancer risk among older adults. (Learn more about foods to eat to help prevent cancer.)
How can the science be so at odds? Because the actual data in Griswold's Lancet paper (as opposed to the summary of findings that frightened wine lovers everywhere) indicates only a tiny, tiny rise in disease risk up until about one alcoholic beverage per day, just like the other studies. "What we show—and Griswold and his colleagues show—is that overall risk appears to go up once you drink more than this," says Wood. Griswold concurs: "The risk increases at a very slow pace to the point where I personally feel confident that if I have one drink a day, I'll be OK. I think our results track well."
The Tipsy Truth
So a little rosé now and then probably isn't helping you live longer, but it's also not dooming you to disease, either. The question is what level of risk you're willing to accept. In response to Griswold's paper, statistician David Spiegelhalter, Ph.D., chair of the Winton Centre for Risk and Evidence Communication at the University of Cambridge and an expert on communicating risk to the public, wrote, "Claiming there is no 'safe' level does not seem an argument for abstention. There is no safe level of driving, but governments do not recommend that people avoid driving. Come to think of it, there is no safe level of living, but nobody would recommend abstention."
Angela Wood put it in visceral terms. According to her research, if you drink more than one but less than two drinks per day, your life expectancy at age 40 might be six months shorter than if you have one or fewer alcoholic beverages daily. Consume between two and four drinks a day and statistically you'll live one to two years less. Spiegelhalter says going from one to two drinks per day is about the same, healthwise, as spending two more hours sitting on the couch (sedentary behavior is known to be bad for your health).
Indeed, the Lancet study's overall global statistics show that if 100,000 adults drink no alcohol for one year, 914 of them stand to develop one of the diseases the paper looks at. If the same 100,000 people consume one drink a day, 918 will develop one of those health problems. That's just four more cases. Drinking two servings of alcohol daily pushes that number up to 977 (63 more diagnoses) and knocking back five drinks per day means 1,252 people will develop a problem (338 more diagnoses).
Also worth noting: since the Lancet study used information from people all over the world—from Portugal to the Democratic Republic of Congo—the risk levels are very broad because they lump together those who reside in both high- and low-income countries, have vastly different diets and lifestyles, and who drink different types of alcohol, from the finest wines to moonshine. They also suffer from different types of diseases. Tuberculosis, for one, is a major cause of alcohol-related death worldwide, but not so much in the U.S. "The study proved that populations don't derive a health benefit from alcohol. But it did not say anything about individuals who are careful about how much they drink," says Katz.
Your own likelihood of developing a particular disease from alcohol is probably quite different from your neighbor's or from that of society as a whole. People also have different variants of a gene called alcohol dehydrogenase that breaks down ethanol, helping your body process it more or less readily. Women, for example, tend to produce about half the alcohol dehydrogenase that men do, the main reason alcohol affects them more. Body size matters too. And everyone's odds of disease are different. "If you're a woman with no cardiovascular risk factors and a strong family history of breast cancer, you're more likely to be harmed, because alcohol appears to contribute to the risk of breast cancer," explains Katz. "But if you don't have a family history of cancer and you do have risk factors for heart disease, you could derive a health benefit from moderate amounts of alcohol." He points out that there are far safer ways to reduce your odds than relying on alcohol—like going for a walk every day. Still, it helps put things in perspective.
The Happiness Factor
Most of us don't have the time or inclination to make mental calculations every time we want a drink. All we care about is relaxing and enjoying a moment of pleasure. And pleasure matters.
Our brains are evolutionarily hard-wired to pursue things like food, sex and alcohol. Drinking triggers the release of feel-good endorphins and increases levels of dopamine, a neurotransmitter that lights up the reward center of your brain. Many other things, like art and music, also stimulate this widespread circuit. Studies have not yet proven that pure hedonic pleasure—that moment of joy you get from tasting a piece of good chocolate or sipping a dirty martini—is linked to better health outcomes. What has been linked, however, is eudaemonia—a Greek word that means a feeling of well-being and fulfillment, of having enjoyed a life well-lived. Studies show that when people experience this kind of contentment, their immune systems function better, their bodies are better able to fight viruses, and levels of inflammation—the kind linked to all sorts of conditions, such as cancer, diabetes, obesity and heart disease—decrease.
One of the few researchers who studies pleasure is Morten Kringelbach, Ph.D., a professor of neuroscience at the universities of Aarhus (in Denmark) and Oxford. He says that alcohol is often a gateway to this type of well-being. "If you were to construct an argument around the benefits of alcohol, it would really be about that social experience of being around others," he says. "Drinking acts as a lubricant. It allows people to be in the moment, and open themselves up to others in a way that they wouldn't have otherwise. As long as they don't overdo it, that's a real positive aspect. There is a great proverb: 'Man is man's medicine.' It could be 'Woman is woman's medicine'; but the key thing is this: what keeps us well is to just be with other people."
Studies on alcohol and health are ongoing and no one pretends to have the final word. So for now, only you know the proper place of alcohol in your life. Wood's view is that, "If you drink, just drink less. If you drink a lot, drink a lot less." And if you choose to drink, enjoy it—preferably in the company of others. "Don't do it for health, but you need not give it up for health either," says Katz. "I drink wine because it's delightful. I'm not relying on that alcohol to make me healthy, but I include it judiciously in my diet because it's a source of great pleasure. And that should be the main motivation for drinking—pleasure."
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