A new study identifies a simple trick that may help people drink less.
According to recent research that was recently published in the scientific journal Addiction, households in the United Kingdom drank wine at a rate of roughly 6.5% less while using smaller (290 ml) glasses than when using bigger (350 ml) glasses.
In this randomized controlled experiment, 260 UK families were chosen from the general population who drank two or more 75cl bottles of wine each week. In two 14-day intervention periods, families were asked to purchase a predetermined quantity of wine to consume at home in either 75cl or 37.5cl bottles, in random order. Additionally, they were randomly assigned to either smaller (290ml) or bigger (350ml) drinking glasses.
After each 14-day intervention period, the amount of wine drunk was recorded by taking pictures of the bought bottles and weighing them on the supplied scales. Using smaller glasses lowered the quantity of wine consumed by roughly 6.5% (253ml per fortnight), though there is some uncertainty around this effect. Drinking from smaller bottles lowered the quantity of wine consumed by 3.6% (146ml per fortnight), however, there is greater uncertainty around this effect.
Wine is the most commonly drunk alcoholic beverage in Europe, and most of it is consumed in homes rather than in bars, restaurants, or pubs. It’s already known that using larger glasses increases the volume of wine sold in restaurants and the size of wine glasses, in general, has increased dramatically over the last three decades. If the effects of wine glass size on consumption are proven reliable, with effects sustained over time, reducing the size of wine glasses used in homes could contribute to policies for reducing drinking.
These policies could include pricing glasses according to capacity to increase the demand for smaller glasses, and regulating glass sizes in bars, restaurants, and other licensed premises to help shift social norms for what constitutes an acceptable glass size for use outside as well as within the home.
Reference: “Impact of wine bottle and glass sizes on wine consumption at home: a within- and between- households randomized controlled trial” by Eleni Mantzari, Minna Ventsel, Jennifer Ferrar, Mark A. Pilling, Gareth J. Hollands and Theresa M. Marteau, 18 July 2022, Addiction.
The study was funded by the Wellcome Trust.