Drinkers beware: You may not be drinking what you think you’re drinking.
According to a study conducted by Brian Wansink, the John S. Dyson Professor of Marketing, Applied Economics and Nutritional Science, college students, adults and even bartenders with years of experience tend to overestimate the amount of alcohol they pour when using short, wide bar glasses.
“Most people think that tall glasses hold more liquid than wide ones of the same volume, and tend to over pour alcohol into short glasses, Wansink said.
Wansink’s study was conducted using 198 college students and 86 bartenders with an average of over six years of experience. Participants in the study were asked to make mixed drinks using 1.5 ounces of vodka, rum, gin and whiskey. Both groups tended to over pour when using short “tumblers” as compared to tall, slender “highball” glasses, even though many of the college students believed they poured less into the short glasses.
Wansink is confident people pour more into short glasses because of what is known as the horizontal-vertical effect.
“When we look at any object we tend to focus on the height of the object, rather than the width. When people pour, they’re looking up and down, not across,” Wansink said.
The results of the study indicate that professional bartenders pour between 20 and 30 percent more alcohol when using short glasses, and the bias associated with the over pouring is only slightly reduced with more experience, concentration or practice.
“As a bartender, you don’t always have time to make sure you pour exactly what you want to into each glass,” said Morton Jacobs, a bartender with two years experience. “Not only that, but if you’re pouring into a short glass in front of a customer, you have to make sure that they think they’re getting enough alcohol in their drink.”
Wansink was surprised by the amount of over pouring done by bartenders with years of practice, even when they had devices on the bottles of alcohol to regulate the amount dispensed.
“We weren’t expecting the bartenders to over pour as much as they did, and even in cases with shot dispensers, what we saw there was double pouring to compensate for the glass looking so small.”
There are three groups Wansink hopes will benefit from the study: people who only drink on occasion; people with alcohol abuse problems; and those in the hospitality industry.
“Hopefully, people will realize when they go out and limit themselves to only a couple of drinks, they’ll now know they may really be consuming a lot more alcohol,” Wansink said.
The surprising results of the study have some people evaluating their own consumption.
“I’m a little shocked by this study actually,” said Amey Sutkowski ’08. “There have probably been many nights where I drank more than I thought.”
The horizontal-vertical illusion created by short glasses is not just limited to alcohol consumption, and Wansink also hopes that people will now knowingly pour more accurate amounts into glasses as a way of becoming healthier.
“We worked with a nursing home and mess halls in the army to see if changing the size of the glass changed how much water the elderly and soldiers drank. Both of these groups need liquid to prevent dehydration.”
Wansink’s research at Cornell focuses on advertisements, personality traits and the packaging of consumer products and their effect on consumption. This study was first published in the British Medical Journal shortly before the holiday season, and was later featured on television shows and in hundreds of newspapers around the world.