Efficacy of a store-based environmental change intervention compared with a delayed treatment control condition on store customers' intake of fruits and vegetables

Objective: The present store-based intervention was designed to promote sales of fruits and vegetables (F&V) to increase intake among store customers - specifically customers of tiendas, small-to-medium-sized Latino food stores. Design: Four tiendas were randomized to a 2-month environmental change intervention or a delayed treatment control condition. Employees and managers were trained to promote F&V sales, including how to implement a food marketing campaign and installing store equipment to promote fresh fruits and vegetables. The primary outcome was self-reported daily intake of F&V among a convenience sample of customers (at least forty per store) collected at baseline prior to randomization and then 4 months later. In addition, changes in availability of F&V in the tiendas, using unobtrusive observational methods, provided evidence of intervention fidelity. Setting: Tiendas in central North Carolina. Subjects: Participants included 179 customers who were recent immigrants from Mexico and Central America. Results: A group-by-time interaction approached significance on daily servings of F & V; intervention customers reported an increase in F&V intake over time and as a function of the intervention (P <= 0.06). Unexpectedly, self-efficacy for consuming more fruits (P <= 0.01) and more vegetables (P <= 0.06) decreased. In our store-level analyses, a group-by-time interaction was observed for availability of fresh and canned vegetables; the intervention increased availability of vegetables but not fruit. Conclusions: Environmental change strategies to promote healthy eating are needed given the rates of obesity and diabetes in the Latino population. A store-based intervention was moderately effective at increasing customers' reported F&V intake. Such strategies can have a public health impact on underserved populations.