Study suggests even light drinking can shorten life
November 28, 2018
By Mike Richman
VA Research Communications
"There has been mounting evidence that finds light drinking isn't good for your health."
A new study finds that consuming alcoholic beverages daily—even at low levels that meet U.S. guidelines for safe drinking—appears to be “detrimental” to your health.
The researchers found that downing one to two drinks at least four days per week was linked to a 20 percent increase in the risk of premature death, compared with drinking three times a week or less. The finding was consistent across the group of more than 400,000 people studied. They ranged in age from 18 to 85, and many were Veterans.
Dr. Sarah Hartz, a psychiatrist at the VA Eastern Kansas Health Care System, led the study. It appeared in November 2018 in the journal Alcoholism: Clinical & Experimental Research. She’s not too surprised by the findings, noting that two large international studies published this year in the British journal The Lancet reached similar conclusions about the dangers of alcohol.
“There has been mounting evidence that finds light drinking isn’t good for your health,” says Hartz, who is also an assistant professor at Washington University in St. Louis.
Hartz and her coauthors note that their results don’t necessarily prove cause and effect. In other words, people who tend to drink more may indeed have shorter lives—but not necessarily as a result of more alcohol consumption. It could be, for example, that those people have harder lives all around, with more stress, which takes a toll on health and longevity. But the researchers did adjust for a range of demographic factors and health diagnoses to try and tease out the direct effects of alcohol.
Another limitation of the study is that it relied on in-person self-reports of alcohol use, which research has shown may lead to under-reporting, compared with anonymous surveys.
The study had many strengths, however. Hartz explains that two major factors separate her study from papers that found light-to-moderate drinking to have health benefits. For one, the researchers studied a much larger population so they could distinguish between groups of drinkers when looking, for instance, at quantity and frequency of alcohol consumption.
“We’re seeing things that we didn’t before because we have access to such large data sets,” she says. “In the past, we couldn’t distinguish between these drinking amounts. To have any statistical power, to be able to reach conclusions that are statistically significant, the larger the data set the more power you have and the easier it is to make conclusions.”
Secondly, Hartz and her colleagues compared drinkers to drinkers.
“Traditionally, the reference group has been people who don’t drink,” she says. “People who don’t drink are different in many, many ways than people who do drink. People who never drink are different culturally from people who drink. For example, I would not have been able to grow up in my culture without ever having a full drink. There are a lot of lifestyle things that go along with your culture—both healthy and unhealthy—which are very hard to tease apart.”
Veterans, general population show similar risk levels
The researchers reviewed two data sets of self-reported alcohol use and mortality follow-up. One set included more than 340,000 people from the National Health Interview Survey (NHIS), a source of information for monitoring the health of U.S. citizens; the other set listed nearly 94,000 Veterans from VA outpatient medical records. The health and survival of the people was tracked between seven and 10 years.
According to the findings, people who drank four or more times a week, even when limiting it to only a drink or two, had about a 20 percent greater risk of dying during the study period. Among those who consumed one to two drinks at a time, the minimum risk level for premature death was drinking 3.2 times a week in the NHIS data and two to three times a week in the VA data. The VA sample had a higher mortality rate based on deaths per 1,000 person-years—13 versus 5—and more people with medical co-conditions.
The findings were consistent in analyses of men, women, and non-smokers.
“It was really surprising that the estimate for minimum risk level for premature death in the Veteran population was so close to the estimate in the general population,” Hartz says. “You would think that they’d be different because the populations are so different and because of the comorbidities with Veterans. Also, the 20 percent numerical estimate is the same for both, which I wouldn’t have guessed.”
She and her team also evaluated deaths due to heart disease and cancer. For heart disease, they found a benefit to drinking, specifically that one to two drinks per day about four days a week seemed to protect against death from heart disease. But drinking every day eliminated those benefits. In terms of death from cancer, any drinking was “detrimental,” she says.
Safe alcohol consumption guidelines vary widely across the globe, according to a study that analyzed recommended levels in 37 countries. Dietary guidelines issued by the U.S. Centers for Disease Control and Prevention (CDC) call for alcohol to be used “in moderation—up to two drinks a day for men and up to one drink a day for women.” A standard drink in the U.S. contains about 14 grams of pure alcohol, meaning men can consume up to 196 grams per week and women 98 and stay within safe guidelines.
The CDC also says one type of an alcoholic drink isn’t necessarily safer than another type. For instance, one 12-ounce beer has about the same amount of alcohol as one 5-ounce glass of wine or 1.5-ounce shot of liquor. The CDC guidelines don’t recommend that people who do not drink should start doing so for any reason.
In contrast, the U.S. safe drinking guidelines are way above the limits in Sweden and Germany. Britain suggests low-risk limits for men almost half that of those in the United States. In France, the recommended limits are more in line with those in the United States: 140 grams (10 drinks) per week for women and 210 grams (15 drinks) per week for men.
Substance use and misuse is a major public health problem and can lead to substance use disorders (SUDs), which include dependencies on alcohol, illicit and prescription drugs, and nicotine. Excessive alcohol use alone leads to nearly 90,000 premature deaths per year. Among service members and Veterans, SUDs often co-occur with health-related problems, such as mental conditions, as well as societal issues like crime and homelessness.
The 'French Paradox’
In the past, some studies have found positive health effects from low-level alcohol consumption. Case in point: One study examined alcohol consumption and the risk of heart attack among men over a 12-year period. Drinking was linked to a lower risk of heart attack, regardless of the type of alcohol. Men who reported drinking up to seven days a week had a lower risk than those who drank less than once a week.
Another study linked light-to-moderate drinking to a lower risk of multiple heart-related outcomes.
Then there’s the “French paradox.” It’s the belief that while the French and American people both maintain a diet high in saturated fats, which can raise the risk of heart disease and stroke, the French have much lower rates of heart disease because they drink a lot of red wine.
More recently, however, studies have challenged the theory that alcohol has health benefits. In one of the studies in The Lancet, researchers reviewed data from dozens of studies on drinking patterns and health outcomes among nearly 600,000 people in 19 advanced countries.
The study team found that drinking more than 100 grams of alcohol per week, the equivalent of about seven drinks, could lead to early death, with life expectancy starting to drop at age 40. The seven-drink-per-week figure was in the range in Hartz’s study in which alcohol can cause serious health problems. Drinking was also tied to a greater risk of stroke, coronary artery disease, and various forms of heart failure. The people in the study had no prior heart disease.
Interestingly, increased consumption was linked to a slightly lower risk of non-fatal heart attack. But that trend must be balanced against the higher risk associated with other serious and potentially fatal types of heart disease, according to the study’s lead author, Dr. Angela Wood of Cambridge University in England.
In Wood’s view, her research and that of Hartz both reached the same conclusion: There are no apparent long-term health benefits from moderate or even light drinking. “Whether low-to-moderate drinking improves social well-being is a different question,” she says.
One way or the other, if you think it’s fine to consume a glass of wine or a beer every evening while winding down at home or in a bar—you may want to think again.