Mind the Gap? An Intensive Longitudinal Study of Between-Person and Within-Person Intention-Behavior Relations.

<bold>Background: </bold>Despite their good intentions, people often do not eat healthily. This is known as the intention-behavior gap. Although the intention-behavior relationship is theorized as a within-person process, most evidence is based on between-person differences.<bold>Purpose: </bold>The purpose of the present study is to investigate the within-person intention-behavior association for unhealthy snack consumption.<bold>Methods: </bold>Young adults (N = 45) participated in an intensive longitudinal study. They reported intentions and snack consumption five times daily for 7 days (n = 1068 observations analyzed).<bold>Results: </bold>A within-person unit difference in intentions was associated with a halving of the number of unhealthy snacks consumed in the following 3 h (CI95 27-70 %). Between-person differences in average intentions did not predict unhealthy snack consumption.<bold>Conclusions: </bold>Consistent with theory, the intention-behavior relation for healthy eating is best understood as a within-person process. Interventions to reduce unhealthy snacking should target times of day when intentions are weakest. [ABSTRACT FROM AUTHOR]