If you’ve ever found yourself getting more drunk on wine than you thought you’d be, there might be a reason for that: According to recent research, wine glasses have gotten a lot bigger over time — and glasses today are actually quite astonishing when it comes to their total capacity. Together with several colleagues, Theresa M. Marteau of the Behavior and Health Research Unit at the University of Cambridge’s Institute of Public Health analyzed how wine glass size has changed over the past three years—and their results suggest not only that the size of wine glasses in England has increased quite a bit since 1700, but moreover, that we’ve seen a pretty incredible increase in recent decades as well.
For the study, which was published in the journal BMJ, Marteau and her colleagues acquired 411 wine glasses spanning the years 1700 to 2017 from five different sources: Wine glasses covering the period between 1700 and 1800 came from the Department of Western Art at the University of Oxford’s Ashmolean Museum of Art and Archaeology; glasses covering 1808 to 1947 came from the Royal Household (apparently a new set of glassware is commissioned for each monarch — I did not know that until now, and I think it’s fascinating); glasses covering 1840 to 2016 (yes, there’s overlap) came from eBay; glasses from 1967 through 2017 came from the catalogues of English glassware manufacturer Dartington Crystal; and lastly, glasses from 2016 came from the department store John Lewis.
Once these glasses had been acquired, the researchers recorded the total capacity of each glass’s bowl; then, they analyzed the data according to size and year — and what they found is honestly pretty shocking. In the 1700s, the average wine glass held around 66 ml of liquid, or about two-and-a-quarter ounces. By 1850, it had about doubled, creeping up to 140 ml, or 4.7 ounces. By 2000, it had more than doubled, coming out to 300 ml, or just over 10 ounces — and by 2016, glasses clocked in at a monumental 450 ml, or about 15.2 ounces.
According to Wine Folly, a standard bottle of wine holds about 750 ml, or just shy of 25 and a half ounces. That means that a wine glass in 2016 is literally capable of holding more than half a bottle of wine.
Now, it’s definitely worth noting that just because a glass can hold that much liquid doesn’t mean that your average pour of wine will result in that much being in your glass at one time; indeed, the researchers are careful to remind us that they haven’t demonstrated a causal link between glass size and the amount of wine people consume. However, as they also observe, it’s not unreasonable to assume that “a larger cup or glass [might increase] the amount of beverage poured and, in turn, the amount drunk” — and other research actually supports that idea.
According to a 2013 study published in the journal Substance Use and Misuse, people tend to overpour by quite a bit when they’re drinking wine at home. As Vinepair points out, there isn’t really a “standard” pour size in the United States in that it’s not regulated by law; however, the National Institute on Alcohol Abuse and Alcoholism (NIAAA) defines one drink of wine as five ounces. The Substance Use and Misuse study, meanwhile, found that people tend to pour 12 percent more wine when they’re using wide glasses, as opposed to narrow ones, as well as when they’re holding the glass versus placing it on the table. We also tend to overpour white more than red.
And here’s the kicker: Even after participants were told that they were overpouring, they continued to pour more than a five-ounce serving anyway.
As you might imagine, all of this can ultimately result in people drinking more wine than they think they are at any given time. What’s more, it muddies the waters with regards to our understanding of binge drinking. According to the NIAAA, binge drinking is defined as “a pattern of drinking that brings blood alcohol concentration levels to 0.08 g/dL,” which usually happens if you drink four or five drinks (depending on a whole bunch of factors, including gender, the alcohol content of whatever you’re drinking, and so on) in a two-hour span of time. But if you’re drinking wine, and your average pour is closer to, say, nine ounces than five, then one glass isn’t equivalent to one drink; according to this handy table from Health.gov, that’s equivalent to almost two drinks (1.8 drinks, to be precise). If you’re only keeping track of the number of drinks you’ve had and not the size of each drink, then you’ll probably end up drinking a lot more than you think you did.
None of this is meant as a shame-y sort of thing, of course; you know your own limits better than anyone else, so, y’know, you do you and all. I do think, however, that all of this is worth keeping in mind, especially if you tend to drink at home or at friends’ houses (that is, places where you’ll likely be pouring for yourself) more than you do at restaurants or bars. Personally,I’d always rather have an accurate idea of how much I’ve drunk than an inaccurate one; I find I overdo it more when I’m not vigilant about monitoring how many glasses I’ve had, and, well… that way lies disaster and pain. And believe you me, hangovers do not get any easier to deal with as you get older. (Indeed, according to most research, hangovers actually get a lot worse as you age.)
And, I mean, hey, at least if you’re drinking wine, you’re more likely to feel chill and confident, right?