Supplemental nutrition assistance program and body weight outcomes: The role of economic contextual factors

► We explored moderating effects of economic contextual factors on the relationship of Supplemental Nutrition Assistance Program (SNAP) and body weight. ► The results showed a statistically significant joint moderating effect of food prices and supermarket/grocery store availability in longitudinal models for both genders. ► A simulated 20% decrease in the price of fruits and vegetables resulted in a larger decrease in BMI among SNAP participants than non-participants for both genders. ► A simulated 20% increase in the availability of supermarkets/grocery stores resulted in a statistically significant difference in the change in BMI by SNAP participation for women only.