The Power of Waiting: How Vending Machine Delays Can Help Stop Obesity

By Ursula Biba

            Obesity is endemic in the United States, and coupled with a poor diet, is one of the strongest risk factors for heart disease, stroke and diabetes. As more people are becoming obese, healthcare workers, scientists and engineers need to get creative to craft innovative interventions. With 1.3 million vending machines currently in the U.S., they are the most popular source of high calorie and nutrient poor snacks in the country. Preventative medicine experts at Rush University Medical Center suggest that consumers are more likely to purchase healthier snacks from a vending machine if there is an order delay placed on the less healthier options, as the delay makes the snacks less desirable. While other vending machine interventions involve eliminating all unhealthy snacks and machines in general, these are unfavorable because of decreased profits. Results from a study comparing different vending machine systems that include taxes on unhealthy snacks, discounts on healthy snacks, time delays on healthy snacks and a combination of all three showcased increased healthy snack purchases in the time delay, healthy snack discount and unhealthy snack tax conditions. These findings propelled the creation of the Delays to Improve Snack Choices System (DISC), in which a bar separates healthy and unhealthy snacks, a 25 second delay is placed on purchasing unhealthy snacks, and a live countdown lets the customer swap an unhealthy snack for a healthier one. In this study, healthy snacks are defined as those with greater than 1 g of fiber per serving, no trans-fat, and less than 250 calories, 35% calories from fat, 350 mg of sodium, 5% of the daily value of saturated fat and 10 g of added sugar per serving. As implementation of the DISC exhibited a 2-5% increase in healthy snack purchases without harming general sales, these machines may be the future of snacking in the U.S. and encourage consumers to make healthier choices more often.


Rush University Medical Center. (2017, March 31). Time delays in vending machines prompt healthier snack choices: Researchers develop new vending machine technology to help improve snack habits. ScienceDaily. Retrieved April 8, 2017 from