This vending machine can convince you to pick a healthier snack

When faced with a 3 p.m. stomach grumble, it’s pretty difficult to pick a Clif bar over a Snickers. But this new vending machine thinks it can help you choose healthier snacks.

The machine dispenses traditional vending machine snacks — unhealthy options like candy bars and chips — on a 25-second time delay. Making people wait longer for more tempting options can change their choices and cause them to pick a lower-calorie snack.

Researchers at the Rush University Medical center designed vending machines with what they call DISC technology: Delays to Improve Snack Choices. During the 25-second delay, people are able to change their choice to something healthier that will be dispensed immediately.

“We wanted to see if we could use this preference for immediate gratification to improve people's vending machine snack choices,” said Brad Appelhans, lead investigator of the study. “This delay yielded a 2 percent to 5 percent increase in the proportion of total purchases from healthy snacks.”

The study, which was funded by the National Institutes of Health, looked at five different ways to try and change vending machine selection habits to healthier snacks. In addition to the 25-second time delay on less healthy snacks, researchers also experimented with a 25-cent discount on health snacks, a 25-cent tax on less healthy snacks, both a 25-second time delay on less healthy snacks and a 25-cent discount on healthier snacks, and a 25-second time delay and 25-cent tax on less healthy snacks. The results of those options were compared with machines where there was no intervention.

The researchers found that the time delays had no impact on total sales volume from the machines. Previous efforts to modify vending machine offerings, like changing inventory completely to healthier snacks, has adversely affected profits for the school or office that collects revenue from the machine.

“Our findings with the DISC vending machine system suggests that relatively brief time delays can nudge people to purchase healthier snacks at least some of the time. The beneficial effect on snack choice is about as large as that seen with discounts,” Appelhans said. “This could be a viable option for vending machine owners to offer good, healthy snack options while keeping their sales and avoiding out-of-pocket costs.”

This story was originally published March 31, 2017 at 3:25 PM with the headline "This vending machine can convince you to pick a healthier snack."