Apples vs. Brownies: A Field Experiment in Rearranging Conference Snacking Buffets to Reduce Short-Term Energy

Apple and Brownie nudge


A standard food setting served daily by caterers at thousands of conference venues, meetings and gatherings is the coffee break buffet featuring some high-energy snack (e.g. brownies) as well as what often seems like an obligatory healthy option (e.g. apples). Knowing how the display of these food items trigger what a person ultimately ends up consuming could be useful in nudging people towards choosing the healthier option. In this field experiment we examined the impact on total energy impact of re-arranging the standard coffee break buffet with respect to (a) piece-size of the high-energy choice (brownies), (b) convenience of consuming the healthy option (apples) and (c) their relative presentation order.


The snack food selections of 391 CEO’s attending a conference in the Danish Opera House were recorded at two identical coffee break buffets featuring apples and brownies. One buffet acting as the control of the experiment was a standard buffet as defined by the caterer. This featured standard sized brownies (approx. 88g) at the front of the buffet table and whole apples in baskets at the back. The intervention buffet featured apples cut in slices of 4 and put in the front of the buffet and brownies cut in half (44g) and put at the back. The buffets were arranged at each end of a first floor foyer in the Opera House and participants self-selected by choosing one of two symmetrical stairs upon entering the symmetrical ground floor foyer. Eight trained research assistants dressed as waiters replenished the buffets and continuously monitored the experiment. The conference participant acted as the basic measurement subject in order not to disturb the naturalness of the setting as well as in accordance with the wishes of the conference organizers. The analysis was done based on the observations and the caloric information of the served items using the caterer’s recipes and the Danish Food Composition Databank ed. 7.01 from the National Food Institute, Denmark.


Visitors eating from the control buffet (n=189) served themselves on average intake of (0,81piece) = 71,4g brownie and 0,25 of piece apple. Visitors at the intervention buffet (n=202) served themselves on (0,57piece) = 50,3g brownie and 0,46 piece of apple.

This amounts to a 30% decrease in brownie consumption and an 84% increase in apple consumption on average per visitor at the intervention buffet compared to the control. Consulting the brownie recipe provided by the caterer and standard nutritional facts for apples the difference in average consumption per visitor amounted to control 1598 KJ and intervention 1182 KJ.


The only hypothesis consistent with the data set was that rearranging the conference buffet with regard to portion size, convenience and presentation order resulted in a significantly lower calorie intake amongst the conference participants eating at the intervention buffet.

Primary Institution – iNudgeyou

Secondary Institutions – Danish Nudging Network, Roskilde University & Aalborg University

Copenhagen airport


There has been given acces to a blogpost about this nudge. Here you can find more relevant information on the nudge.

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More litterature

Skov, L. R., Lourenco, S., Hansen, G. L., Mikkelsen, B. E., & Schofield, C. (2013). Choice architecture as a means to change eating behaviour in self-service settings: a systematic review. Obesity Reviews, 14(3), 187-196.

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