Honorary Fellow Professor Dame Theresa Marteau is the senior author on a study that shows that the amount of wine sold by pubs and pubs is reduced by just under 8% when the largest serving of wine by the glass is taken away.
Alcohol consumption is the fifth largest contributor to premature death and disease worldwide. In 2016 it was estimated to have caused approximately 3 million deaths worldwide.
In the same way that reducing portion sizes reduces the amount of food that people eat, this research could suggest one way of persuading customers to drink less alcohol.
First author Dr Eleni Mantzari, from the University of Cambridge, said:
“It looks like when the largest serving size of wine by the glass was unavailable, people shifted towards the smaller options, but didn’t then drink the equivalent amount of wine.
“People tend to consume a specific number of ‘units’ – in this case glasses – regardless of portion size. So, someone might decide at the outset they’ll limit themselves to a couple of glasses of wine, and with less alcohol in each glass they drink less overall.”
Twenty premises – mainly pubs – contributed data to the Cambridge team. Over a four-week period these premises did not sell the largest serving of wine – usually 250ml – by the glass.
The study found that there was an average (mean) decrease of 420 ml of wine sold per day per venue which is a 7.6% decrease.
There was no evidence that people drank more of other alcoholic drinks such as beer or cider instead. Nor did the participating premises see a decrease in their total daily revenue.
Professor Marteau, recently named as one of the top female scientists in the world by research.com, said:
“Although the reduction in the amount of wine sold at each premise was relatively small, even a small reduction could make a meaningful contribution to population health.”
The researchers note that, although the intervention would potentially be acceptable to pub or bar managers, given there was no evidence that it can result in a loss in revenue, a nationwide policy would likely be resisted by the alcohol industry given its potential to reduce sales of targeted drinks. Public support for such a policy would depend on its effectiveness and how clearly this was communicated.
The research was funded by Wellcome.
Mantzari, E et al. Impact on wine sales of removing the largest serving size by the glass: an A-B-A reversal trial in 21 pubs, bars and restaurants in England. PLOS Medicine; DOI: 10.1371/journal.pmed.1004313
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