Under pressure to act because of rising childhood obesity, some supermarkets have moved snacks away from the till, where people queuing – often with children – are tempted to put them in the shopping basket as they wait their turn.

Research shows the positioning of products at the checkout or on the end of aisles increases their sales. The findings suggest that many families who stop adding sweets and crisps at the counter appear not to buy them at all.

The government-funded study, published in the journal Plos Medicine, found that 76% fewer annual purchases of sugary confectionery and crisps were bought and eaten on the go from supermarkets that do not stock them at checkouts than at those that do.

The study used commercially held data from 7,500 shoppers who recorded food bought and eaten on the go during 2016-17 from supermarkets with and without checkout food policies. On the go purchases are often impulsive and can be the result of children pestering their parents.

The researchers, from Cambridge, Stirling and Newcastle universities, also looked at how purchases of less healthy, common checkout foods that were brought home – rather than eaten on the go – changed after the implementation of checkout policies. They used data from more than 30,000 UK households from 12 months before to 12 months after implementation.

They found that removing the unhealthy snacks from the checkout was associated with an immediate 17% reduction in purchases. After a year, shoppers were still purchasing 15% fewer of the items compared with when no policy was in place.

“Our findings suggest that by removing sweets and crisps from the checkout, supermarkets can have a positive influence on the types of purchases their shoppers make,” said Dr Katrine Ejlerskov, the study’s first author.

“This would be a relatively simple intervention with the potential to encourage healthier eating. Many of these purchases may have been impulse buys, so if the shopper doesn’t pick up a chocolate bar at the till, it may be one less chocolate bar that they consume.”

Dr Jean Adams, a senior lecturer in dietary public health research at the University of Cambridge, said: “It may seem obvious that removing unhealthy food options from the checkout would reduce the amount that people buy, but it is evidence such as this that helps build the case for government interventions to improve unhealthy behaviours.”

The government promised to consult on removing snacks from supermarket checkouts as part of its latest obesity plan. Bryony Sinclair, a senior policy manager at the World Cancer Research Fund, welcomed the study. “Displaying sugary food and drinks at checkouts, tempting shoppers to make unhealthy last-minute decisions, is unacceptable,” she said.

“These evidence-informed policies can then be implemented by governments to create environments that support healthier choices, as eating too much sugar can lead to weight gain, and being overweight or obese increases the risk of 12 different types of cancer.”

The Guardian

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