Promoting healthful food purchases through in-store interventions: Empirical evidence from rural food deserts

Effective ways to promote healthful food intake in rural areas are understudied. The paper evaluated whether a two-component, in-store intervention designed to encourage healthy food purchases was associated with improved healthfulness scores of food items purchased by shoppers in rural food deserts. One component introduced a point-of-sales label that assigned a single numerical score to each food item facilitating direct comparisons of the product's nutrition with those of other products shelved around it. The other component was a one-day nutrition education workshop promoted within the store. Interventions took place in 2015 at two stores in rural counties in the U.S. Midwest. Four stores in similar communities were selected as the control group. We applied a difference-in-difference model to estimate changes in the healthfulness of food items purchased attributable to the intervention among shoppers at the treatment stores (n = 486) and control stores (n = 10,759) using store transaction data. Healthfulness of food items was measured in terms of food scores published by the Environmental Working Group on a 1-10 scale. Both components had minimal impacts on the scores, although 0.2 and 0.1 points increases in the score per item and score per dollar were statistically significant at the 1% level respectively. A year after the intervention, these small effects of the intervention further diminished compared to the immediately after implementation. Results suggest the average effects of intervention across the study communities had limited practical significance but benefited some rural residents who were exposed to the intervention.