Maintaining Sales While Offering Healthier Options in Vending Machines: A Case Study

While colleges and universities commonly indicate a desire to support students in making healthy eating choices, a persistent concern relates to the potential of decreased revenue. However, a study recently published in the journal Appetite found: “In a university setting, the redesign of vending machines using principles of choice architecture and point-of-purchase labeling resulted in much higher rates of healthier products purchased without compromising financial performance.”  

Researchers Joseph Viana, Stephanie Leonard, Bob Kitay, Daryl Ansel, Peter Angelis, and Wendelin Slusser conducted their study over a two-month period using about 100 vending machines on a university campus. This is notable because among the limited research on vending machines in a university setting, most studies are based on fewer than 10 machines and less than one month’s sales data.  

So how did these researchers find success? They based their interventions on previous studies, including branding vending machines as part of a “Health Campus Initiative,” using individual stickers to denote healthier products, and grouping healthier products in designated rows at eye level. The control group of comparison machines maintained their inventory, which did include some healthy options. Additionally, the price of popular candy bars was raised from $1 to $1.25 in both the intervention and comparison machines. Some other studies have experimented with lowering the prices for healthy options, but this study’s opposite approach may have helped maintain revenue. 

The researchers worked with multiple campus departments to ensure outcomes would be viable. University nutritionists reviewed all products to ensure they were correctly classified as healthier options. Initially, the criteria had been: less than 250 calories, 35% calories from fat, 10% calories from saturated fat, 35% sugar by weight, and 360 mg of sodium. However, some items were reclassified “if they contained corn syrup or other added sugars as one of the first three ingredients, any trans fats, or were fried. In addition, unsalted nut and seed products that did not meet the initial nutritional criteria because of their high caloric and fat content were reclassified as healthier products.”  

As previous studies have noted the importance of engaging the university’s vending operators to ensure healthier vending policies are sustainable, the researchers also worked closely with the on-campus department that maintains the vending machines. That unit provided sales data and helped design the interventions as part of the university-wide Healthy Campus Initiative. “A strength of this study was its use of a multidisciplinary partnership, which ensured the intervention was based in science and policy while being operationally feasible,” the authors wrote. 

Using point-of-purchase surveys, the researchers also revealed that most customers approach a vending machine without a particular product in mind (63%). This finding is a new addition to the literature and “suggests a sizable portion of customers approach the machine with an open mind and can be influenced by interventions that promote healthier vending choices,” the authors asserted. During the study, counts of healthier items purchased from an intervention machine were eight times higher than that of a comparison machine. Additionally, “undecided customers who purchased from an intervention machine were significantly more likely to buy a healthier product (50%) than undecided customers who purchased from comparison machines (10%).” It is important to note that this study was conducted at only one institution; however, it provides evidence to suggest that there may be a way to meet the “twin goals” of maintaining sales and promoting healthful choices among the campus community.  

Reference: 

Viana, J., Leonard, S.A., Kitay, B., Ansel, D., Angelis, P., & Slusser, W. (2018). Healthier vending machines in a university setting: Effective and financially sustainable. Appetite, 121, 263–267. 


Steps to Implementing Healthier Food Standards

  1. Review and circulate information among stakeholders about the magnitude of the
    obesity epidemic, current food options available to the university community,
    existing institutional food standards, and benefits of healthful eating. 
  2. Identify champions to conduct educational presentations to administrators, establish short-term and long-term goals, and prepare end users. Professionals may find it beneficial to engage supporters from unlikely places, such as nearby elementary schools, hospital cafeterias, juvenile detention facilities, or retirement homes that already have such standards in place.  
  3. Draft plans of revised institutional standards, marketing plans, and stakeholder training initiatives. This may include reviewing vending contract language and soliciting customer concerns.  
  4. Implement new practices, gain customer acceptance of changes, and familiarize
    staff with assistance and resources available. Ensure there are mechanisms in place to facilitate two-way communication with front-line personnel.  
  5. Evaluate objectives and goals, solicit feedback from operations staff, make necessary adjustments, and expand program as is feasible. Institutions or units that adopt new standards will have knowledge about successes and challenges that can be shared across the professional community. 
Based on:

Robles, B., Wood, M., Kimmons, J., & Kuo, T. (2013). Comparison of nutrition standards and other recommended procurement practices for improving institutional food offerings in Los Angeles County, 2010–2012. Advances in Nutrition, 4, 191–202. 

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