Healthy checkout lines and sales worries

Looking for an interesting movie about nudging in the supermarket? Here it is.

Tempting snacks near the checkout line can be hard to resist. Yoni Freedhoff's blog included a post about healthy checkout aisles at a few stores in the US. Unhealthy snacks such as candy bars were removed from the aisle and replaced by (dried) fruit, vegetables and toys that encourage children to be active such as hula hoops. The movie shows customers who are happy (less nagging by children) and store managers who seem to be surprised by its success.

Easy access to healthier snacks may indeed impact consumer choices, as our recently published study showed. Nevertheless, our study took place in a hospital staff canteen where sales were not of big concern.

This transformation of junk food checkout lines into healthier lines took place in 2011. I would love to see data showing the effectiveness of this nudge throughout time. Interestingly, one store manager in the movie mentions the higher profit margins of some healthier items (such as the jump rope) compared to a candy bar. It appears that the success of 'a healthy options aisle' depends on the 'replacement assortment'. Apparently, customers need or want to be tempted and give in to something, whether it is chocolate or a toy. Hopefully, sales did not drop after the first excitement. After all, without substantial sales, I am afraid this experiment would not continue for a long time.

Impulsive snacking at the checkout counter: nudging consumers towards healthier 'grab-and-go'-snacks

Candy aisle near checkout 

Tempting snacks placed right near the checkout counter can be hard to resist. Even though you know buying one is not in your best interest, they catch attention. These high-profit 'grap-and-go' snacks are particularly hard to ignore at the end of a shopping trip after making dozens of decisions. Even at my local shoe store, they tried to tempt me in buying candy (see picture).

In our recent paper published in BMC Public Health, we (that is Hans van Trijp, Kai Otten and myself) report two nudging studies on whether assortment structure and accessibility of healthier snacks influences consumer choices. The idea was that providing a larger assortment of healthier snacks and putting them on top of shelves makes these snacks more salient, attractive and convenient, leading hopefully to higher sales.

To test this idea, we first carried out a study among students in which we asked them to make a hypothetical choice from a shelf displayed at their computer screen. The results of this study showed that when the majority of snacks is healthy, students were are more likely to choose such a snack. Although this may seem obvious, they were equally satisfied with their choice and did not feel restricted.

However, lab studies do not always provide reliable predictions about how people behave in real-life. Therefore, we conducted a  field experiment in hospital 'De Gelderse Vallei'. We now put an actual snack shelf near the checkout of the staff canteen. Each week, an alternative snack assortment was on display. The assortment included either 25% or 75% healthy snacks. We also altered their place on the shelf (either on the higher shelves or the lower shelves). On completion of the study, we also conducted a brief survey among employees.

When 75% of the assortment consisted of healthy snacks, sales of healthy snacks were higher. In contrast to our expectations, putting healthy snacks at the most convenient (top) shelf space did not impact consumer choices and sales. It could be that our manipulation was not strong enough (see picture). Interestingly, the majority of surveyed employees did not notice assortment changes. When asked, however, they preferred the shelf displays including the larger variety of healthy snacks.

Overall, these studies show the size of a healthy assortment of snacks matters. A relative large assortment of healthy snacks is able to influence consumer choices. However, we do not know whether this intervention really leads to better snacking habits at the longer term. Moreover, these types of interventions are typically more successful in canteens than those in restaurants and grocery stores, where financial interests are at stake.  


While not all nudges are effective (see for example our nudging study among children), this nudge might be worth to give a try. Without forbidding any foods, a larger assortment of healthy snacks may catch consumer attention and even seduce them to purchase. 


Nudging paper in BMC Public Health: Healthy snacking at the checkout counter: a lab and field study 


van Kleef E, Otten K, & van Trijp HC (2012). Healthy snacks at the checkout counter: A lab and field study on the impact of shelf arrangement and assortment structure on consumer choices. BMC public health, 12 (1) PMID: 23231863