To answer those questions you do need science, and lucky for us, science recently discovered the answers! For a forthcoming article in the journal Addiction, researchers analyzed surveys filled out by 13,000 people -- hailing from 18 countries -- who found themselves drunk and in the emergency room for injury. The research was supported by a grant from the National Institute of Alcohol Abuse and Alcoholism.
In what should come as a shock to nobody, the more you drink, the more likely you are to hurt yourself. A person who has consumed 3 drinks in the past six hours is about 4.6 times as likely to end up in the E.R. as someone who hasn't drunk at all. Even a single drink roughly doubles your odds of going to the hospital.
"Patients were asked about the cause of injury bringing them to the emergency department (categorized as falls, traffic, violence, other), drinking within six hours prior to the injury event, and drinking during the same six-hour period the previous week," author Cheryl Cherpitel and her four co-authors explain. Cherpitel is a researcher Alcohol Research Group, a program of the Public Health Institute.
They converted alcohol consumption quantities to standard drinks of 16 ml ethanol. Some of the people in the study drank a lot. So the authors were able to plot the relationship between drinks and hospital visits all the way up to a mind-boggling 30 drinks. This may sound like a lot, but remember that there is a not insignificant number of people for whom 10 drinks a day is standard. After having those ten drinks, your odds of going to the E.R. have increased by a factor of 10.
Interestingly, the relationship tends to flatten out from there, which makes sense if you think about it. After 15 or 20 drinks, you're at a very high likelihood of passing out. And once you've passed out you're unable to hurt yourself. You're either going to wake up with an epic hangover the next day, or you will choke on your own vomit and die. Either way, you're not showing up in this data.
But the startling finding in these numbers is that after three drinks, womens' likelihood of getting injured increases far more rapidly than mens'. At ten drinks, the average man's risk of seriously injuring himself has risen tenfold. But a woman's risk after the same number of drinks is about 14 times greater. That gap only widens as the drinking intensifies.
Why the greater injury risk for women? Duke University's Philip Cook points out that "generally speaking the effects of ingesting X ounces of ethanol in 6 hours depends on weight but also gender (and other factors). Women tend to be more reactive to alcohol, achieving a higher BAC for given level of drinking and body weight." In other words, 10 drinks are likely to have a greater effect on the average woman than on the average man.
The study also found a significant difference in the types of injury reported by the drunken E.R. patients. Interpersonal-violence - in other words, hitting each other - had a significantly stronger relationship with increased drinking than either traffic accidents or falls. The increased likelihood of violent injury was apparent and statistically significant after even one drink. In short, a single drink nearly quadruples your chances of getting in a fight and going to the hospital.
From a policy standpoint, Cherpitel said that an important factor is the context of drinking. Different countries, and even different regions of a single country, have very different cultural attitudes about getting drunk. Cherpitel says that in the U.S., for instance, Californians exhibit drinking patterns similar to what you see in Mediterranean countries, where alcohol is consumed frequently, but in small quantities with meals. Binge drinking, on the other hand, is more of a staple of life in the South and upper Midwest.
From a policy standpoint, Cherpitel emphasizes that there's no one-size-fits-all approach to alcohol regulation. Different drinking cultures produce different drinking outcomes - including hospital visits. And the stark differences in injury risk for women and men suggest that some populations may be at greater risk for alcohol-related harm than others.