I’m a doctor and I’ve got a tip that can help you curb the amount of wine you drink

Large wine glasses, which I first noticed in the US, have always struck me as a touch overindulgent. But would you believe that smaller wine glasses can help curb drinking?

A Cambridge University study has found removing the largest glasses in bars – in most cases the 250ml ones – can reduce the average amount of wine sold by just under 8%. It’s not that big a change, but offering only 175ml glasses could nudge customers to drink less alcohol, claim the researchers.

Alcohol consumption is the fifth largest cause of premature death and disease worldwide. In 2016 it caused approximately three million deaths worldwide. There are many factors influencing how much we drink, from advertising and labelling to availability and cost – and now glass size.

The Cambridge team studied 21 licensed premises (mainly pubs) to see whether removing their largest serving of wine by the glass for four weeks would have an impact on how much wine – the most commonly drunk alcoholic drink in the UK and Europe – is consumed. Twenty of the premises completed the experiment and were included in the final analysis. The researchers found removing the largest wine glass serving led to an average decrease of 420ml of wine sold per day per venue – about 7.6%.

There was no evidence that sales of beer and cider increased. Instead, it suggested people didn’t compensate for their reduced wine consumption by drinking more of these. First author Dr Eleni Mantzari 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, added: “It’s worth remembering no level of alcohol consumption is considered safe for health, with even light consumption contributing to the development of many cancers.

“Although the reduction in the amount of wine sold at each premises was relatively small, even a small reduction could make a meaningful contribution to population health.”

In general, consumers prefer information-based messaging, such as health warning labels, to reductions in serving or package sizes. However, in this study, managers at just four of the 21 premises reported receiving complaints from customers. Good move.