Does transportation mode modify associations between distance to food store, fruit and vegetable consumption, and BMI in low-income neighborhoods?

BACKGROUND: A consistent body of research has shown that the neighborhood food environment is associated with fruit and vegetable (F&V) consumption and obesity in deprived neighborhoods in the United States. However, these studies have often neglected to consider how transportation can moderate associations between food accessibility and diet-related outcomes.
OBJECTIVE: This study examined associations between distance to primary food store, fruit and vegetable consumption, and BMI and whether mode of transportation to the primary food store moderates this relation.
DESIGN: Cross-sectional data from the baseline wave of the Philadelphia Neighborhood Food Environment Study were used. A telephone survey of adult (≥18 y of age) household primary food shoppers residing in 2 Philadelphia neighborhoods was conducted (n = 1440).
RESULTS: In a bivariate linear regression analysis, distance to primary food store did not predict F&V consumption (β = 0.04; 95% CI: -0.00, 0.09). Linear regression analysis stratified by transportation mode to the main F&V store showed no difference in F&V consumption between car, public, and multimodal transportation users. Compared with respondents using multimodal transportation, those using public transit had a significantly lower BMI (β = -1.31; 95% CI: -2.50, -0.10), whereas those using an automobile did not (β = -0.41; 95% CI: -1.36, 0.54).
CONCLUSIONS: The assumption that using an automobile to access food stores results in increased F&V consumption was not confirmed. Significant associations were found for the relation between transportation mode and BMI. Theory-based mechanisms explaining relationships between the primary transportation mode used to access food stores and BMI should be further explored.