Social approval bias in self-reported fruit and vegetable intake after presentation of a normative message in college students.

OBJECTIVE: To determine the accuracy of self-reported data regarding Fruit and Vegetable (FV) intake in college students at Utah State University after being presented with a descriptive normative message.

INTERVENTION: Participants (N = 167) were recruited from general education courses and asked to complete a baseline survey containing a FV screener from the National Cancer Institute. They were then randomized to receive one of four messages one week after the initial survey and asked to immediately complete the same FV screener. The Control group received no FV message. The Recommendation group received a message that the recommendation for FV is 4-5 cups per day. The two normative groups received a message that either 80% of students ate more (Low) or less (High) FV than they did, regardless of actual intake, in addition to the recommended intake.

ANALYSIS: Repeated measures ANOVA was used to assess differences in reported FV intake and perceived FV intake of peers between the first and second assessment.

RESULTS AND CONCLUSIONS: Those receiving the message that they were in the lowest 20th percentile of intake reported a half-cup increase in self-reported FV intake and a one-cup increase in perception of peers' intake (p = 0.037 and p=<0.001, respectively). No significant differences were observed in other groups. These results indicate that normative messaging may influence self-reported FV intake and perception of peer intake of college students when this message indicates that the participant is in the lowest percentile of their peers.