Changing the places where people do unhealthy things can help many people make better choices and lower the risk of diseases. One way to do this is by making the sizes of the things people buy smaller, like the amount of alcohol they get. The effect of modifying the available range of serving sizes of wine in a real-world setting is unknown.
A new study aimed to assess the impact on the volume of wine sold by removing the largest serving size by the glass from the options available in licensed premises.
The new study led by a team at the University of Cambridge has discovered that taking away the largest serving of wine by the glass – in most cases, the 250ml option – led to an average reduction in the amount of wine sold at pubs and bars of just under 8%.
Scientists noted, “While only modest, the finding could provide one way of nudging customers to drink less alcohol and have an impact at a population level.”
Researchers studied 21 licensed places, primarily pubs, in England. They wanted to see if not offering the largest serving of wine for four weeks would change how much wine people bought. Wine is a popular alcoholic drink in the UK and Europe. Twenty places followed the study, and the researchers looked at the results.
After considering factors like the day of the week and total revenue, the researchers found that not offering the most extensive wine glass led to an average decrease of 420ml of wine sold per day per place, which is a 7.6% decrease.
There was no sign that people bought more beer or cider, suggesting they didn’t compensate for drinking less wine. It also didn’t affect the overall daily earnings of the places, meaning they didn’t lose money by not offering the largest wine size. However, it’s important to note that the study must be designed to provide stronger evidence.
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.”
Professor Dame Theresa Marteau, the study’s senior author and an Honorary Fellow at Christ’s College Cambridge, added:Â “It’s worth remembering that no level of alcohol consumption is considered safe for health, with even light consumption contributing to the development of many cancers. Although the amount of wine sold at each premise was relatively small, even a small reduction could make a meaningful contribution to population health.”
Research indicates that people prefer interventions that provide information, like health warning labels, rather than reducing the size of servings or packages. However, in this study, only four out of the 21 places reported customer complaints.
The researchers point out that while pub or bar managers may find this intervention acceptable, as it doesn’t lead to a loss in revenue, the alcohol industry may resist a nationwide policy. This resistance could be because it can potentially reduce sales of specific drinks. Whether the public supports such a policy would depend on how effective it is and how clearly its benefits are communicated.
Journal Reference:
- 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