Glass Shape Affects Drinking Speed
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Glass Shape Affects Drinking Speed

You're having cocktails with clients or a celebratory beer with your boss – safe bet you don't want to get sloshed. So you try to sip slowly to pace yourself, because you know the minute that glass gets low, Billy the Bartender will be right there to offer you a second (or third) and your drinking mates will likely say, "Sure! Have another!"

Still, it can be tough to gauge sip sizes and frequency, especially if you're nervous, anxious, or the conversation stalls. According to a new study, however, drink volume and speed may be even more difficult to estimate if you're tipping back a curved glass.

Researchers from the United Kingdom's University of Bristol recruited 159 social drinkers with no history of alcoholism and had them sip beer from both a rounded and a straight-sided glass. On a whole, the subjects drank a whopping 60-percent slower from the straight glass than the curved one.

"We think this was due to difficulties in judging the midpoint of the curved glass," says Angela Attwood, lead study author and a researcher at the University of Bristol's School of Experimental Psychology. "People tend to use height in their judgment of volume. If you place a ruler next to a straight-sided glass, the halfway point in terms of height will be pretty much the same as the halfway point in terms of volume," she explains. Not so for the curved glass. "People often underestimate the midpoint, thinking it's lower down than it actually is."

Attwood says misreading the midpoint might make you glug a beer faster – and lead you to drink more in total – because you think you've imbibed less than you actually have or you feel like you're drinking more slowly than the rest of the group.

Of course, you're not going to give the bartender a specific glass-type request (please don't), but the next time you sip from a Stella Artois chalice or curvy pilsner glass – and your mission is staying on the right side of sober – it might suit you well to deliberately take it a few notches slower. Let your boss be the one who wishes he'd held back.