After a particularly long day at the office, when it's too late for happy hour, a drink may sound like the most pleasant relief in the world.
But if you work longer than 48 hours a week, it's more likely that a drink or two may turn into three, four, five, or more, according to a study released Jan. 13 by the British Medical Journal.
And while a harmless glass of wine or whiskey might help take the edge off, too much comes with risks beyond a hangover. Working adults are more at risk from their drinking habits than they might think - a recent CDC report found that binge drinking kills more middle-aged Americans than college students.
This should be of particular concern to Americans, who work longer hours than people in most other developed nations. The percentage of professional and middle income men and women who have been working more than 50 hours a week has been on the rise since 1979.
So does working a lot make you want to drink?
There's good evidence that it does.
Researchers looked at approximately 81 different studies to see both the relationship between working and drinking in more than 333,000 people and the changes that occur in that relationship when people start working long hours (that prospective group included just over 100,000 people).
Risky drinking in this case was classified as more than 21 drinks a week for men and more than 14 drinks a week for women (these are based on standard public health guidelines, but if they seem stingy, check out the NIH's classification of safe drinking).
The researchers found that people who worked more than 48 hours a week were 11% more likely to have risky drinking habits than people who worked 35-40 hours.
They found similar results when looking at a group of people they followed over a period of time. In those studies, people who started working those same long hours at some point during the study were 12% more likely to develop risky drinking habits than the 35-to-40-hours-a-week group. That finding helps provide some evidence for a causal relationship between longer working hours and risky drinking, though it doesn't prove one.
"In absolute terms... the difference between these groups was relatively small," the researchers acknowledge, in their paper. "Risky alcohol use was only 0.8 and 0.7 percentage points higher" in the people working longer hours.
Still, if the relationship between working long hours and risky drinking is indeed causal, even a small increase in risk would mean millions more people engaging in a troubling public health behavior - all because they are working too many hours.
Long hours may not cause dangerous drinking, but why is there a relationship between those two things at all?
This meta-analysis can't answer that question, but the researchers suggest that the same personalities that make people heavy drinkers might also be the personalities attracted to competitive jobs that require long hours - people who like novelty, risk, and are attracted to the "work hard, play hard" culture.
Cassandra A. Okechukwu, an assistant professor at the Harvard School of Public Health, suggests in an editorial accompanying the study that time constraints may leave workers with "few choices but to rely on alcohol as a rapid mental and physical analgesic to alleviate the stresses and strains associated with working long hours."
In other words, people are self-medicating.
The answer may also be in some combination of those explanations, or it might be very different for each person.
The authors use their findings to argue that the European Union (studies included European and North American participants) should be cautious about granting exceptions to the European Union directive that people shouldn't work more than 48 hours a week, including overtime.
They say that those exceptions could lead to poor performance, high stress, injuries, and expensive health problems further down the road.
Okechukwu describes the health concerns raised by this research as something "that we cannot afford to ignore."