Although studies demonstrate that dietary interventions for healthy adults can result in beneficial dietary changes, few studies examine when and how people change in response to these interventions, particularly in rural populations. The purpose of this study was to examine patterns of change over time in healthy eating behaviors in midlife and older women in response to a one-year health-promoting intervention, and to examine what predictors (perceived benefits, barriers, self-efficacy, and family support for healthy eating) influence the changes during the intervention and follow-up. Data for this secondary analysis were from the Wellness for Women community-based trial. Women (N ¼ 225) between the ages of 50e69 in rural Nebraska, U.S.A., were recruited. A repeated-measures experimental design was used with randomization of two rural counties to intervention (tailored newsletter) or comparison (standard newsletter) groups. Eating behavior was measured by the Healthy Eating Index. The predictor variables were assessed using standard measures. Data analysis was done using latent growth curve modeling. The tailored newsletter group was successful in improving their healthy eating behavior compared to the standard newsletter group during the one-year intervention, at the end of the intervention, and during the follow-up phase. Family support at the end of the intervention was positively associated with healthy eating at the end of the intervention. Perceived barriers had the strongest impact on healthy eating behavior at all time points. Compared to participants in the standard newsletter group, those in the tailored newsletter group perceived more family support and fewer barriers for healthy eating at the end of the intervention (mediation effects). Based on these findings, both family support and perceived barriers should be central components of interventions focused on healthy eating behavior in rural midlife and older women.