Americans who drink alcohol have endured years of ambiguous studies, some telling them moderate drinking might help them, others saying it will definitely hurt them.
So is having a drink with dinner good for our health or bad? After a series of sweeping meta-studies, the latest published in March, science is getting closer to a definitive answer: Yes.
Moderate drinking raises the odds, very slightly but very definitely, that the drinker will contract any of a number of diseases, or die a violent death.
Modest alcohol consumption may also confer modest health benefits, especially to the heart, and especially among older people, who face a greater risk of heart disease.
On the second point, the scientific community remains divided.
“If you’re over the age of 50 or 60 and you enjoy a drink or two a day, I don’t think you need to worry about it, I don’t think you need to feel guilty about it,” said Emmanuela Gakidou, professor of health metrics sciences at the University of Washington.
Gakidou was the senior author of a massive 2018 study, co-written by more than 500 researchers and published in the Lancet, that explored more than one thousand prior studies and data sets on alcohol.
The study found that, at one drink a day, a drinker’s risk of developing one of 23 health problems increased by 0.5 percent. At two drinks a day, the risk rose by 7 percent.
Those are minute risks. And yet, the study produced headlines such as “Safest level of alcohol consumption is none.”
Given what scientists know now, that statement is technically true. Some of the health risks that attend even moderate drinking are well-documented.
“Everything related to violence and accidents goes up with alcohol use,” Gakidou said, including drunken driving, household accidents and suicide. Moderate drinking increases cancer risks, albeit not by much.
But alcohol may also confer benefits. Many studies have suggested moderate drinking lowers the risk of heart disease and strokes. Other studies have reached the opposite conclusion.
“When you look at all of them, there’s a lot of noise there,” Gakidou said. But if you imagine all of the studies as dots plotted on a chart, “the cloud of points is mostly on the protective side, rather than the harmful side.”
Not so many years ago, scientists and civilians believed moderate drinking delivered definite health benefits. Such positive thinking may have peaked in a 1991 episode of the CBS newsmagazine 60 Minutes, which posited the notion that red wine boosted heart health. Wine sales soared.
As it turned out, the science behind those studies was flawed.
Yes, studies found that people who drank red wine lived longer than people who did not. But those wine-drinkers enjoyed all sorts of other healthy habits and native advantages: income and education, balanced diets, healthy weights, a fondness for exercise, and superior healthcare.
Many nondrinkers, by contrast, weren’t drinking for a reason: They were already sick, had disabilities, or suffered from alcoholism.
“As time goes by, it gets worse,” said Tim Stockwell, a scientist at the Canadian Institute for Substance Use Research. As study subjects age, the teetotaler category “fills up with people who stopped drinking because they had health issues.”
Thus, when researchers compared the health of drinkers and nondrinkers, the drinkers often came out ahead.
Stockwell co-authored a new meta-study in a prestigious American Medical Association journal, which analyzed more than 100 prior studies to correct for those biases. The review found that health risks began when women drank 25 grams of daily alcohol, less than two drinks. Risks mounted for men who drank 45 grams of alcohol daily, a little over three drinks.
All risk is relative, and the risks a drinker assumes by cracking a beer are not large. On average, an adult who downs six drinks a week will die two to three months earlier than a nondrinker.
“It’s a low risk, but it’s a significant risk,” Stockwell said. “My revolutionary thought is that you just tell consumers what the risk is, in ways that they can get their head around.”
Many drinkers, of course, would happily trade a few months of life for a glass of wine at dinner each night.
The big studies sparked visceral reactions on both sides, from drinkers and nondrinkers alike. Some readers felt defrauded by decades of studies suggesting that moderate drinking was unquestionably good for you. Others felt the science, and the press coverage, vastly inflated the dangers.
“Given the pleasure presumably associated with moderate drinking, claiming there is no ‘safe’ level does not seem an argument for abstention,” one British statistician opined of the 2018 study. “There is no safe level of driving, but the government does not recommend that people avoid driving.”
The anger probably drew more from alarmist headlines than from the studies themselves, which presented their findings in understated medical-journal jargon.
“You measure a risk, and you announce that it’s a risk, and then people get mad at you for telling them what to do,” Stockwell quipped.
Gakidou, who is Greek, spoke to The Hill from Greece. “And if you talk to people in my culture, in Greece, if you tell them not to drink, you are not very popular,” she said. “I think people around the world, they want confirmation that their approach to drink is the healthy one.”
Nearly every adult drinks in Denmark, the 2018 meta-study found, while the average Portuguese man downs seven drinks a day. Average life expectancy is 82 in Denmark and 81 in Portugal, about a decade higher than the global average of 72, data points that illustrate the complexities of studying alcohol.
One big unknown, and a glimmer of hope for drinkers, is the relationship between drinking and heart attacks and strokes.
The only way to prove whether drinking raises or lowers those risks is to run a controlled experiment that compares drinkers and nondrinkers by randomly assigning subjects to drink or abstain.
To run such a clinical trial is trickier than it sounds: It could mean asking a subject to drink, knowing the proven link between drinking and, say, vehicular death. And proving the long-term effects of alcohol, by definition, requires a long-term study.
“You really need years,” said William Kerr, senior scientist at the nonprofit Alcohol Research Group. “And it becomes challenging for people to stay on the program.”
Yet, in the last decade, the National Institutes of Health launched just such a study, dispensing $100 million for scientists to confirm or refute that alcohol could be part of a healthy diet.
And then, in 2018, the study was shut down. A New York Times investigation found that much of the funding had come from the alcohol industry, hardly an impartial party.
And so the potential health benefits of modest alcohol consumption remain a mystery, while the modest health risks have gained broad acceptance.
Canada released new alcohol guidelines this year, advising no amount of alcohol is safe and recommending no more than two drinks a week.
U.S. guidelines suggest no more than one drink a day for women or two a day for men. Some researchers would like the guidelines revised to suggest no more than a drink a day for anyone.
Kerr cautions, however, that many Americans may balk at a drink-a-day limit.
“Some people just don’t see that as drinking,” he said.
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