Background: The present empirical studies test the effectiveness of a
nudge aimed to reduce soda consumption. Based on the center stage effect, we hypothesized that
people would choose smaller cups of soda when the small cup size was presented in the middle of
a choice set (medium-small-large) rather than at the edge (small-medium-large). Additionally,
health goals were taken into account, and it was expected that the nudge would only be
effective for people who have the goal to be healthy. Methods: In 2 studies participants were
randomized into a nudge or a control condition and asked to select a soda cup. Health goals
were assessed before participants came into the lab. Logistic regression analyses were
performed to analyze the results. Findings: Participants in the nudge conditions were
significantly more likely to choose the small cup compared to those in the control conditions.
The effect tended to be stronger for people with stronger health goals. Discussion: Simple
adjustments in the presentation order of cup sizes can significantly affect unhealthy soda
consumption. The influence of personal goals on effectiveness will be discussed.
