Objective To assess the impact of the Child and Adult Care Food Program (CACFP) on diet and 3 health outcomes -- weight-for-height status, dental caries (tooth decay) score, and number of days of illness -- among preschool children attending 2 urban day care centers. Design Dietary intake and health outcome measures were assessed and compared for children attending 2 day-care centers in an urban community. Data were obtained for 14 days of dietary intake, which were analyzed for energy and 15 nutrients and 6 food groups; anthropometric measures, including weight-for-height; dental caries; and days of illness. Subjects/setting Forty 3- to 5-year-old black children from 2 day-care centers participated. One center participates in the CACFP. At the other center, children bring all meals and snacks from home. Statistical analyses performed Data from the 2 groups of children were compared using parametric and nonparametric t tests. Results Children receiving CACFP meals at day care had significantly higher mean daily intakes of vitamin A (804 +/- 191 vs 595 +/- 268 retinol equivalents), riboflavin (1.45 +/- 0.32 vs 1.21 +/- 0.22 mg), and calcium (714 +/- 180 vs 503 +/- 143 mg) than the children who brought all of their meals and snacks from home. Children who received CACFP meals also consumed significantly more servings of milk (2.9 +/- 0.9 servings vs 1.5 +/- 0.7) and vegetables (1.8 +/- 0.5 vs 1.2 +/- 0.5 servings) and significantly fewer servings of fats/sweets (4.6 +/- 1.3 vs 5.4 +/- 1.1 servings) than children who brought their meals. Weight-for-height status and dental caries scores did not differ between the 2 groups. Children from the center participating in the CACFP have significantly fewer days of illness (median 6.5 vs 10.5 days) than children from the nonparticipating center. Applications Nutritious meals provided by the CACFP can improve diets and may promote health among young, urban children. Registered dietitians can contribute to food assistance programs by intervening to enhance the quality of meals served and by examining the impact of participation on measures of diet quality and diet-related health outcomes. (author abstract)