Objective: To explore the impact of the new Special Supplemental Nutrition Program for Women, Infants and Children (WIC) food package on WIC participant consumption of fruit, vegetables, whole-grain food, and lower-fat milk. Design: Telephone surveys of cross-sectional samples of California WIC families before and after the changes to the food package. Participants: Random samples of pregnant or postpartum women and/or caregivers of children enrolled in WIC: 3,004 in September, 2009; 2,996 in March, 2010. Main Outcome Measures: Consumption of fruit, vegetables, whole-grain food, and lower-fat milk. Analysis: Comparisons of outcome variables were made by examining the differences by time point, adjusted for sociodemographic variables, using ANOVA (for means) or logistic regression (for percentages). Results: Following the changes to the WIC food package, consumption of whole-grain food increased by 17.3 percentage points, a 51% increase over baseline. Caregivers and children who usually consumed whole milk decreased by 15.7 and 19.7 percentage points, respectively, a 60%-63% reduction over baseline. Accompanying increases in lower-fat milk consumption were demonstrated. Small but significant increases in consumption of fruits and vegetables were also observed. Conclusions and Implications: Federal policy changes to the WIC program had the intended effect of increasing consumption of the prescribed food items. (Contains 2 tables.)