The size of glass used for serving wine can influence the amount of wine drunk, suggests new research from the University of Cambridge.
The study found that when restaurants served wine in 370ml rather than 300ml glasses they sold more wine, and tended to sell less when they used 250ml glasses.
The same effects were not seen in bars, because they are less likely to sell wine by the bottle.
The research was done in conjuction with the National Institute of Health Research who say that the negative effects of drinking alcohol need to be taken seriously, and that one option could be banning big glasses. Alcohol is the fifth largest contributor to early death in high income countries and the seventh world-wide.
The researchers say that wine glasses have increased almost seven fold in size over the last 300 years, with the most marked increase being since 1990.
In the last thirty years, the average wine glass has doubled in size.
They also note that over the past three centuries the amount of wine consumed in England has more than quadrupled but the number of wine consumers has stayed the same.
Wine in a bar or restaurant is sold by a fixed serving size or by the bottle or carafe.
Restaurants are more likely to sell wine by the bottle than bars.
A carried out by researchers at the Behaviour and Health Research Unit, University of Cambridge, suggested that serving wine in larger wine glasses – while keeping the measure the same – led to a significant increase in the amount of wine sold.
To provide a robust estimate of the effect size of wine glass size on sales the Cambridge team brought together all of their previously published datasets from studies carried out between 2015 and 2018 at bars and restaurants in Cambridge.
They used 300ml glasses as the reference level against which to compare differences in consumption.
In restaurants, when glass size was increased to 370ml, wine sales increased by 7.3%.
“Pouring wine from a bottle or a carafe, as happens for most wine sold in restaurants, allows people to pour more than a standard serving size, and this effect may increase with the size of the glass and the bottle.
The researchers also found similar internal patterns to those reported in previous studies, namely lower sales of wine on warmer days and much higher sales on Fridays and Saturdays than on Mondays.
The researchers found no significant differences in wine sales by glass size in bars.
Senior author of the report, Professor Dame Theresa Marteau said:
“If we are serious about tackling the negative effects of drinking alcohol, then we will need to understand the factors that influence how much we consume. Given our findings, regulating wine glass size is one option that might be considered for inclusion in local licensing regulations for reducing drinking outside the home.”
“This interesting study suggests a new alcohol policy approach by looking at how the size of wine glasses may influence how much we drink. It shows how our drinking environment can impact on the way we drink and help us to understand how to develop a drinking environment which helps us to drink less.”